src/mode.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd is copyright (C) 2002-2006 ChatSpike-Dev.
   6  *                       E-mail:
   7  *                <brain@chatspike.net>
   8  *                <Craig@chatspike.net>
   9  *
  10  * Written by Craig Edwards, Craig McLure, and others.
  11  * This program is free but copyrighted software; see
  12  *            the file COPYING for details.
  13  *
  14  * ---------------------------------------------------
  15  */
  16
  17 using namespace std;
  18
  19 #include "inspircd_config.h"
  20 #include "inspircd.h"
  21 #include "configreader.h"
  22 #include <unistd.h>
  23 #include <sys/errno.h>
  24 #include <time.h>
  25 #include <string>
  26 #include "hash_map.h"
  27 #include <map>
  28 #include <sstream>
  29 #include <vector>
  30 #include <deque>
  31 #include "connection.h"
  32 #include "users.h"
  33 #include "ctables.h"
  34 #include "globals.h"
  35 #include "modules.h"
  36 #include "dynamic.h"
  37 #include "wildcard.h"
  38 #include "message.h"
  39 #include "commands.h"
  40 #include "xline.h"
  41 #include "inspstring.h"
  42 #include "helperfuncs.h"
  43 #include "mode.h"
  44
  45 /* +s (secret) */
  46 #include "modes/cmode_s.h"
  47 /* +p (private) */
  48 #include "modes/cmode_p.h"
  49 /* +b (bans) */
  50 #include "modes/cmode_b.h"
  51 /* +m (moderated) */
  52 #include "modes/cmode_m.h"
  53 /* +t (only (half) ops can change topic) */
  54 #include "modes/cmode_t.h"
  55 /* +n (no external messages) */
  56 #include "modes/cmode_n.h"
  57
  58 extern int MODCOUNT;
  59 extern std::vector<Module*> modules;
  60 extern std::vector<ircd_module*> factory;
  61 extern InspIRCd* ServerInstance;
  62 extern ServerConfig* Config;
  63
  64 extern time_t TIME;
  65
  66 ModeHandler::ModeHandler(char modeletter, int parameters_on, int parameters_off, bool listmode, ModeType type, bool operonly)
  67         : mode(modeletter), n_params_on(parameters_on), n_params_off(parameters_off), list(listmode), m_type(type), oper(operonly)
  68 {
  69 }
  70
  71 ModeHandler::~ModeHandler()
  72 {
  73 }
  74
  75 bool ModeHandler::IsListMode()
  76 {
  77         return list;
  78 }
  79
  80 ModeType ModeHandler::GetModeType()
  81 {
  82         return m_type;
  83 }
  84
  85 bool ModeHandler::NeedsOper()
  86 {
  87         return oper;
  88 }
  89
  90 int ModeHandler::GetNumParams(bool adding)
  91 {
  92         return adding ? n_params_on : n_params_off;
  93 }
  94
  95 char ModeHandler::GetModeChar()
  96 {
  97         return mode;
  98 }
  99
 100 ModeAction ModeHandler::OnModeChange(userrec* source, userrec* dest, chanrec* channel, std::string &parameter, bool adding)
 101 {
 102         return MODEACTION_DENY;
 103 }
 104
 105 void ModeHandler::DisplayList(userrec* user, chanrec* channel)
 106 {
 107 }
 108
 109 bool ModeHandler::CheckTimeStamp(time_t theirs, time_t ours, const std::string &their_param, const std::string &our_param, chanrec* channel)
 110 {
 111         return (ours < theirs);
 112 }
 113
 114 ModeWatcher::ModeWatcher(char modeletter, ModeType type) : mode(modeletter), m_type(type)
 115 {
 116 }
 117
 118 ModeWatcher::~ModeWatcher()
 119 {
 120 }
 121
 122 char ModeWatcher::GetModeChar()
 123 {
 124         return mode;
 125 }
 126
 127 ModeType ModeWatcher::GetModeType()
 128 {
 129         return m_type;
 130 }
 131
 132 bool ModeWatcher::BeforeMode(userrec* source, userrec* dest, chanrec* channel, std::string &parameter, bool adding, ModeType type)
 133 {
 134         return true;
 135 }
 136
 137 void ModeWatcher::AfterMode(userrec* source, userrec* dest, chanrec* channel, const std::string &parameter, bool adding, ModeType type)
 138 {
 139 }
 140
 141 userrec* ModeParser::SanityChecks(userrec *user,char *dest,chanrec *chan,int status)
 142 {
 143         userrec *d;
 144         if ((!user) || (!dest) || (!chan) || (!*dest))
 145         {
 146                 return NULL;
 147         }
 148         d = Find(dest);
 149         if (!d)
 150         {
 151                 WriteServ(user->fd,"401 %s %s :No such nick/channel",user->nick, dest);
 152                 return NULL;
 153         }
 154         return d;
 155 }
 156
 157 char* ModeParser::Grant(userrec *d,chanrec *chan,int MASK)
 158 {
 159         if (!chan)
 160                 return NULL;
 161
 162         for (std::vector<ucrec*>::const_iterator i = d->chans.begin(); i != d->chans.end(); i++)
 163         {
 164                 if (((ucrec*)(*i))->channel == chan)
 165                 {
 166                         if (((ucrec*)(*i))->uc_modes & MASK)
 167                         {
 168                                 return NULL;
 169                         }
 170                         ((ucrec*)(*i))->uc_modes = ((ucrec*)(*i))->uc_modes | MASK;
 171                         switch (MASK)
 172                         {
 173                                 case UCMODE_OP:
 174                                         ((ucrec*)(*i))->channel->AddOppedUser(d);
 175                                 break;
 176                                 case UCMODE_HOP:
 177                                         ((ucrec*)(*i))->channel->AddHalfoppedUser(d);
 178                                 break;
 179                                 case UCMODE_VOICE:
 180                                         ((ucrec*)(*i))->channel->AddVoicedUser(d);
 181                                 break;
 182                         }
 183                         log(DEBUG,"grant: %s %s",((ucrec*)(*i))->channel->name,d->nick);
 184                         return d->nick;
 185                 }
 186         }
 187         return NULL;
 188 }
 189
 190 char* ModeParser::Revoke(userrec *d,chanrec *chan,int MASK)
 191 {
 192         if (!chan)
 193                 return NULL;
 194
 195         for (std::vector<ucrec*>::const_iterator i = d->chans.begin(); i != d->chans.end(); i++)
 196         {
 197                 if (((ucrec*)(*i))->channel == chan)
 198                 {
 199                         if ((((ucrec*)(*i))->uc_modes & MASK) == 0)
 200                         {
 201                                 return NULL;
 202                         }
 203                         ((ucrec*)(*i))->uc_modes ^= MASK;
 204                         switch (MASK)
 205                         {
 206                                 case UCMODE_OP:
 207                                         ((ucrec*)(*i))->channel->DelOppedUser(d);
 208                                 break;
 209                                 case UCMODE_HOP:
 210                                         ((ucrec*)(*i))->channel->DelHalfoppedUser(d);
 211                                 break;
 212                                 case UCMODE_VOICE:
 213                                         ((ucrec*)(*i))->channel->DelVoicedUser(d);
 214                                 break;
 215                         }
 216                         log(DEBUG,"revoke: %s %s",((ucrec*)(*i))->channel->name,d->nick);
 217                         return d->nick;
 218                 }
 219         }
 220         return NULL;
 221 }
 222
 223 char* ModeParser::GiveOps(userrec *user,char *dest,chanrec *chan,int status)
 224 {
 225         userrec *d = this->SanityChecks(user,dest,chan,status);
 226
 227         if (d)
 228         {
 229                 if (IS_LOCAL(user))
 230                 {
 231                         int MOD_RESULT = 0;
 232                         FOREACH_RESULT(I_OnAccessCheck,OnAccessCheck(user,d,chan,AC_OP));
 233
 234                         if (MOD_RESULT == ACR_DENY)
 235                                 return NULL;
 236                         if (MOD_RESULT == ACR_DEFAULT)
 237                         {
 238                                 if ((status < STATUS_OP) && (!is_uline(user->server)))
 239                                 {
 240                                         WriteServ(user->fd,"482 %s %s :You're not a channel operator",user->nick, chan->name);
 241                                         return NULL;
 242                                 }
 243                         }
 244                 }
 245
 246                 return this->Grant(d,chan,UCMODE_OP);
 247         }
 248         return NULL;
 249 }
 250
 251 char* ModeParser::GiveHops(userrec *user,char *dest,chanrec *chan,int status)
 252 {
 253         userrec *d = this->SanityChecks(user,dest,chan,status);
 254
 255         if (d)
 256         {
 257                 if (IS_LOCAL(user))
 258                 {
 259                         int MOD_RESULT = 0;
 260                         FOREACH_RESULT(I_OnAccessCheck,OnAccessCheck(user,d,chan,AC_HALFOP));
 261
 262                         if (MOD_RESULT == ACR_DENY)
 263                                 return NULL;
 264                         if (MOD_RESULT == ACR_DEFAULT)
 265                         {
 266                                 if ((status < STATUS_OP) && (!is_uline(user->server)))
 267                                 {
 268                                         WriteServ(user->fd,"482 %s %s :You're not a channel operator",user->nick, chan->name);
 269                                         return NULL;
 270                                 }
 271                         }
 272                 }
 273
 274                 return this->Grant(d,chan,UCMODE_HOP);
 275         }
 276         return NULL;
 277 }
 278
 279 char* ModeParser::GiveVoice(userrec *user,char *dest,chanrec *chan,int status)
 280 {
 281         userrec *d = this->SanityChecks(user,dest,chan,status);
 282
 283         if (d)
 284         {
 285                 if (IS_LOCAL(user))
 286                 {
 287                         int MOD_RESULT = 0;
 288                         FOREACH_RESULT(I_OnAccessCheck,OnAccessCheck(user,d,chan,AC_VOICE));
 289
 290                         if (MOD_RESULT == ACR_DENY)
 291                                 return NULL;
 292                         if (MOD_RESULT == ACR_DEFAULT)
 293                         {
 294                                 if ((status < STATUS_HOP) && (!is_uline(user->server)))
 295                                 {
 296                                         WriteServ(user->fd,"482 %s %s :You must be at least a half-operator to change modes on this channel",user->nick, chan->name);
 297                                         return NULL;
 298                                 }
 299                         }
 300                 }
 301
 302                 return this->Grant(d,chan,UCMODE_VOICE);
 303         }
 304         return NULL;
 305 }
 306
 307 char* ModeParser::TakeOps(userrec *user,char *dest,chanrec *chan,int status)
 308 {
 309         userrec *d = this->SanityChecks(user,dest,chan,status);
 310
 311         if (d)
 312         {
 313                 if (IS_LOCAL(user))
 314                 {
 315                         int MOD_RESULT = 0;
 316                         FOREACH_RESULT(I_OnAccessCheck,OnAccessCheck(user,d,chan,AC_DEOP));
 317
 318                         if (MOD_RESULT == ACR_DENY)
 319                                 return NULL;
 320                         if (MOD_RESULT == ACR_DEFAULT)
 321                         {
 322                                 if ((status < STATUS_OP) && (!is_uline(user->server)) && (IS_LOCAL(user)))
 323                                 {
 324                                         WriteServ(user->fd,"482 %s %s :You are not a channel operator",user->nick, chan->name);
 325                                         return NULL;
 326                                 }
 327                         }
 328                 }
 329
 330                 return this->Revoke(d,chan,UCMODE_OP);
 331         }
 332         return NULL;
 333 }
 334
 335 char* ModeParser::TakeHops(userrec *user,char *dest,chanrec *chan,int status)
 336 {
 337         userrec *d = this->SanityChecks(user,dest,chan,status);
 338
 339         if (d)
 340         {
 341                 if (IS_LOCAL(user))
 342                 {
 343                         int MOD_RESULT = 0;
 344                         FOREACH_RESULT(I_OnAccessCheck,OnAccessCheck(user,d,chan,AC_DEHALFOP));
 345
 346                         if (MOD_RESULT == ACR_DENY)
 347                                 return NULL;
 348                         if (MOD_RESULT == ACR_DEFAULT)
 349                         {
 350                                 /* Tweak by Brain suggested by w00t, allow a halfop to dehalfop themselves */
 351                                 if ((user != d) && ((status < STATUS_OP) && (!is_uline(user->server))))
 352                                 {
 353                                         WriteServ(user->fd,"482 %s %s :You are not a channel operator",user->nick, chan->name);
 354                                         return NULL;
 355                                 }
 356                         }
 357                 }
 358
 359                 return this->Revoke(d,chan,UCMODE_HOP);
 360         }
 361         return NULL;
 362 }
 363
 364 char* ModeParser::TakeVoice(userrec *user,char *dest,chanrec *chan,int status)
 365 {
 366         userrec *d = this->SanityChecks(user,dest,chan,status);
 367
 368         if (d)
 369         {
 370                 if (IS_LOCAL(user))
 371                 {
 372                         int MOD_RESULT = 0;
 373                         FOREACH_RESULT(I_OnAccessCheck,OnAccessCheck(user,d,chan,AC_DEVOICE));
 374
 375                         if (MOD_RESULT == ACR_DENY)
 376                                 return NULL;
 377                         if (MOD_RESULT == ACR_DEFAULT)
 378                         {
 379                                 if ((status < STATUS_HOP) && (!is_uline(user->server)))
 380                                 {
 381                                         WriteServ(user->fd,"482 %s %s :You must be at least a half-operator to change modes on this channel",user->nick, chan->name);
 382                                         return NULL;
 383                                 }
 384                         }
 385                 }
 386
 387                 return this->Revoke(d,chan,UCMODE_VOICE);
 388         }
 389         return NULL;
 390 }
 391
 392 void ModeParser::Process(char **parameters, int pcnt, userrec *user, bool servermode)
 393 {
 394         std::string target = parameters[0];
 395         ModeType type = MODETYPE_USER;
 396         unsigned char mask = 0;
 397         chanrec* targetchannel = FindChan(parameters[0]);
 398         userrec* targetuser  = Find(parameters[0]);
 399
 400         log(DEBUG,"ModeParser::Process start");
 401
 402         if (pcnt > 1)
 403         {
 404                 if (targetchannel)
 405                 {
 406                         log(DEBUG,"Target type is CHANNEL");
 407                         type = MODETYPE_CHANNEL;
 408                         mask = MASK_CHANNEL;
 409                 }
 410                 else if (targetuser)
 411                 {
 412                         log(DEBUG,"Target type is USER");
 413                         type = MODETYPE_USER;
 414                         mask = MASK_USER;
 415                 }
 416                 else
 417                 {
 418                         /* No such nick/channel */
 419                         log(DEBUG,"Target type is UNKNOWN, bailing");
 420                         return;
 421                 }
 422                 std::string mode_sequence = parameters[1];
 423                 std::string parameter = "";
 424                 std::ostringstream parameter_list;
 425                 std::string output_sequence = "";
 426                 bool adding = true, state_change = false;
 427                 int handler_id = 0;
 428                 int parameter_counter = 2; /* Index of first parameter */
 429
 430                 for (std::string::const_iterator letter = mode_sequence.begin(); letter != mode_sequence.end(); letter++)
 431                 {
 432                         unsigned char modechar = *letter;
 433
 434                         switch (modechar)
 435                         {
 436
 437                                 log(DEBUG,"Iterate mode letter %c",modechar);
 438
 439                                 /* NB:
 440                                  * For + and - mode characters, we don't just stick the character into the output sequence.
 441                                  * This is because the user may do something dumb, like: +-+ooo or +oo-+. To prevent this
 442                                  * appearing in the output sequence, we store a flag which says there was a state change,
 443                                  * which is set on any + or -, however, the + or - that we finish on is only appended to
 444                                  * the output stream in the event it is followed by a non "+ or -" character, such as o or v.
 445                                  */
 446                                 case '+':
 447                                         /* The following expression prevents: +o+o nick nick, compressing it to +oo nick nick,
 448                                          * however, will allow the + if it is the first item in the sequence, regardless.
 449                                          */
 450                                         if ((!adding) || (!output_sequence.length()))
 451                                                 state_change = true;
 452                                         adding = true;
 453                                         continue;
 454                                 break;
 455                                 case '-':
 456                                         if ((adding) || (!output_sequence.length()))
 457                                                 state_change = true;
 458                                         adding = false;
 459                                         continue;
 460                                 break;
 461                                 default:
 462
 463                                         /**
 464                                          * Watch carefully for the sleight of hand trick.
 465                                          * 65 is the ascii value of 'A'. We take this from
 466                                          * the char we're looking at to get a number between
 467                                          * 1 and 127. We then logic-or it to get the hashed
 468                                          * position, dependent on wether its a channel or
 469                                          * a user mode. This is a little stranger, but a lot
 470                                          * faster, than using a map of pairs.
 471                                          */
 472                                         handler_id = (modechar - 65) | mask;
 473
 474                                         if (modehandlers[handler_id])
 475                                         {
 476                                                 bool abort = false;
 477
 478                                                 log(DEBUG,"Found a ModeHandler* for mode %c",modechar);
 479
 480                                                 for (ModeWatchIter watchers = modewatchers[handler_id].begin(); watchers != modewatchers[handler_id].end(); watchers++)
 481                                                 {
 482                                                         log(DEBUG,"Call a ModeWatcher*");
 483                                                         if ((*watchers)->BeforeMode(user, targetuser, targetchannel, parameter, adding, type) == MODEACTION_DENY)
 484                                                                 abort = true;
 485                                                 }
 486                                                 if ((modehandlers[handler_id]->GetModeType() == type) && (!abort))
 487                                                 {
 488                                                         log(DEBUG,"Modetype match, calling handler");
 489
 490                                                         if (modehandlers[handler_id]->GetNumParams(adding))
 491                                                         {
 492                                                                 log(DEBUG,"ModeHandler* for this mode says it has parameters. pcnt=%d parameter_counter=%d",pcnt,parameter_counter);
 493
 494                                                                 if (parameter_counter < pcnt)
 495                                                                 {
 496                                                                         parameter = parameters[parameter_counter++];
 497                                                                 }
 498                                                                 else
 499                                                                 {
 500                                                                         /* No parameter, continue to the next mode */
 501                                                                         continue;
 502                                                                 }
 503                                                         }
 504                                                         ModeAction ma = modehandlers[handler_id]->OnModeChange(user, targetuser, targetchannel, parameter, adding);
 505
 506                                                         if ((modehandlers[handler_id]->GetNumParams(adding)) && (parameter == ""))
 507                                                         {
 508                                                                 /* The handler nuked the parameter and they are supposed to have one.
 509                                                                  * We CANT continue now, even if they actually returned MODEACTION_ALLOW,
 510                                                                  * so we bail to the next mode character.
 511                                                                  */
 512                                                                 continue;
 513                                                         }
 514
 515                                                         if (ma == MODEACTION_ALLOW)
 516                                                         {
 517                                                                 log(DEBUG,"ModeAction was allow");
 518
 519                                                                 /* We're about to output a valid mode letter - was there previously a pending state-change? */
 520                                                                 if (state_change)
 521                                                                 {
 522                                                                         log(DEBUG,"Appending state change");
 523                                                                         output_sequence.append(adding ? "+" : "-");
 524                                                                 }
 525
 526                                                                 /* Add the mode letter */
 527                                                                 output_sequence.push_back(modechar);
 528                                                                 log(DEBUG,"Added mode letter to output sequence, sequence now: '%s'",output_sequence.c_str());
 529
 530                                                                 /* Is there a valid parameter for this mode? If so add it to the parameter list */
 531                                                                 if ((modehandlers[handler_id]->GetNumParams(adding)) && (parameter != ""))
 532                                                                 {
 533                                                                         log(DEBUG,"Added parameter to parameter_list, list now: '%s'",parameter_list.str().c_str());
 534                                                                         parameter_list << " " << parameter;
 535                                                                 }
 536
 537                                                                 /* Call all the AfterMode events in the mode watchers for this mode */
 538                                                                 for (ModeWatchIter watchers = modewatchers[handler_id].begin(); watchers != modewatchers[handler_id].end(); watchers++)
 539                                                                 {
 540                                                                         log(DEBUG,"Called a ModeWatcher* after event");
 541                                                                         (*watchers)->AfterMode(user, targetuser, targetchannel, parameter, adding, type);
 542                                                                 }
 543
 544                                                                 /* Reset the state change flag */
 545                                                                 state_change = false;
 546                                                         }
 547                                                 }
 548                                         }
 549                                 break;
 550                         }
 551                 }
 552                 /* Was there at least one valid mode in the sequence? */
 553                 if (output_sequence != "")
 554                 {
 555                         if (servermode)
 556                         {
 557                                 if (type == MODETYPE_CHANNEL)
 558                                 {
 559                                         WriteChannelWithServ(Config->ServerName,targetchannel,"MODE %s %s%s",targetchannel->name,output_sequence.c_str(),parameter_list.str().c_str());
 560                                 }
 561                         }
 562                         else
 563                         {
 564                                 if (type == MODETYPE_CHANNEL)
 565                                 {
 566                                         log(DEBUG,"Write output sequence and parameters to channel: %s %s%s",targetchannel->name,output_sequence.c_str(),parameter_list.str().c_str());
 567                                         WriteChannel(targetchannel,user,"MODE %s %s%s",targetchannel->name,output_sequence.c_str(),parameter_list.str().c_str());
 568                                         FOREACH_MOD(I_OnMode,OnMode(user, targetchannel, TYPE_CHANNEL, output_sequence + parameter_list.str()));
 569                                 }
 570                         }
 571                 }
 572         }
 573 }
 574
 575
 576 void cmd_mode::Handle (char **parameters, int pcnt, userrec *user)
 577 {
 578         if (!user)
 579                 return;
 580
 581         ServerInstance->ModeGrok->Process(parameters, pcnt, user, false);
 582
 583         return;
 584 }
 585
 586 void ModeParser::CleanMask(std::string &mask)
 587 {
 588         std::string::size_type pos_of_pling = mask.find_first_of('!');
 589         std::string::size_type pos_of_at = mask.find_first_of('@');
 590         std::string::size_type pos_of_dot = mask.find_first_of('.');
 591         std::string::size_type pos_of_colon = mask.find_first_of(':'); /* Because ipv6 addresses are colon delimited */
 592
 593         if ((pos_of_pling == std::string::npos) && (pos_of_at == std::string::npos))
 594         {
 595                 /* Just a nick, or just a host */
 596                 if ((pos_of_dot == std::string::npos) && (pos_of_colon == std::string::npos))
 597                 {
 598                         /* It has no '.' in it, it must be a nick. */
 599                         mask.append("!*@*");
 600                 }
 601                 else
 602                 {
 603                         /* Got a dot in it? Has to be a host */
 604                         mask = "*!*@" + mask;
 605                 }
 606         }
 607         else if ((pos_of_pling == std::string::npos) && (pos_of_at != std::string::npos))
 608         {
 609                 /* Has an @ but no !, its a user@host */
 610                  mask = "*!" + mask;
 611         }
 612         else if ((pos_of_pling != std::string::npos) && (pos_of_at == std::string::npos))
 613         {
 614                 /* Has a ! but no @, it must be a nick!ident */
 615                 mask.append("@*");
 616         }
 617 }
 618
 619 bool ModeParser::AddMode(ModeHandler* mh, unsigned const char modeletter)
 620 {
 621         unsigned char mask = 0;
 622         unsigned char pos = 0;
 623
 624         /* Yes, i know, this might let people declare modes like '_' or '^'.
 625          * If they do that, thats their problem, and if i ever EVER see an
 626          * official InspIRCd developer do that, i'll beat them with a paddle!
 627          */
 628         if ((modeletter < 'A') || (modeletter > 'z'))
 629                 return false;
 630
 631         mh->GetModeType() == MODETYPE_USER ? mask = MASK_USER : mask = MASK_CHANNEL;
 632         pos = (modeletter-65) | mask;
 633
 634         if (modehandlers[pos])
 635                 return false;
 636
 637         modehandlers[pos] = mh;
 638         log(DEBUG,"ModeParser::AddMode: added mode %c",modeletter);
 639         return true;
 640 }
 641
 642 ModeParser::ModeParser()
 643 {
 644         /* Clear mode list */
 645         memset(modehandlers, 0, sizeof(modehandlers));
 646         memset(modewatchers, 0, sizeof(modewatchers));
 647
 648         /* Initialise the RFC mode letters */
 649         this->AddMode(new ModeChannelSecret, 's');
 650         this->AddMode(new ModeChannelPrivate, 'p');
 651         this->AddMode(new ModeChannelBan, 'b');
 652         this->AddMode(new ModeChannelModerated, 'm');
 653         this->AddMode(new ModeChannelTopicOps, 't');
 654         this->AddMode(new ModeChannelNoExternal, 'n');
 655 }
 656