citadel/citserver.c

   1 /* $Id$ */
   2 #include "sysdep.h"
   3 #include <stdlib.h>
   4 #include <unistd.h>
   5 #include <stdio.h>
   6 #include <fcntl.h>
   7 #include <signal.h>
   8 #include <time.h>
   9 #include <ctype.h>
  10 #include <string.h>
  11 #include <errno.h>
  12 #include <limits.h>
  13 #ifdef HAVE_PTHREAD_H
  14 #include <pthread.h>
  15 #endif
  16 #include <syslog.h>
  17 #include <dlfcn.h>
  18 #include <netdb.h>
  19 #include <sys/socket.h>
  20 #include <netinet/in.h>
  21 #include <arpa/inet.h>
  22 #include "citadel.h"
  23 #include "server.h"
  24 #include "sysdep_decls.h"
  25 #include "citserver.h"
  26 #include "config.h"
  27 #include "database.h"
  28 #include "housekeeping.h"
  29 #include "user_ops.h"
  30 #include "logging.h"
  31 #include "support.h"
  32 #include "msgbase.h"
  33 #include "locate_host.h"
  34 #include "room_ops.h"
  35 #include "file_ops.h"
  36 #include "dynloader.h"
  37 #include "policy.h"
  38 #include "control.h"
  39 #include "tools.h"
  40
  41 struct CitContext *ContextList = NULL;
  42 int ScheduledShutdown = 0;
  43 int do_defrag = 0;
  44
  45 /*
  46  * Various things that need to be initialized at startup
  47  */
  48 void master_startup(void) {
  49         lprintf(7, "Opening databases\n");
  50         open_databases();
  51
  52         if (do_defrag)
  53                 defrag_databases();
  54
  55         lprintf(7, "Checking floor reference counts\n");
  56         check_ref_counts();
  57
  58         lprintf(7, "Creating base rooms (if necessary)\n");
  59         create_room(BASEROOM, 0, "", 0);
  60         create_room(AIDEROOM, 4, "", 0);
  61         create_room(config.c_twitroom, 0, "", 0);
  62         }
  63
  64 /*
  65  * Cleanup routine to be called when the server is shutting down.
  66  */
  67 void master_cleanup(void) {
  68         struct CleanupFunctionHook *fcn;
  69
  70         /* Cancel all running sessions */
  71         lprintf(7, "Cancelling running sessions...\n");
  72         while (ContextList != NULL) {
  73                 kill_session(ContextList->cs_pid);
  74                 }
  75
  76         /* Run any cleanup routines registered by loadable modules */
  77         for (fcn = CleanupHookTable; fcn != NULL; fcn = fcn->next) {
  78                 (*fcn->h_function_pointer)();
  79                 }
  80
  81         /* Close databases */
  82         lprintf(7, "Closing databases\n");
  83         close_databases();
  84
  85         /* Do system-dependent stuff */
  86         sysdep_master_cleanup();
  87
  88         /* Now go away. */
  89         lprintf(3, "citserver: exiting.\n");
  90         fflush(stdout); fflush(stderr);
  91         exit(0);
  92         }
  93
  94
  95 /*
  96  * Free any per-session data allocated by modules or whatever
  97  */
  98 void deallocate_user_data(struct CitContext *con)
  99 {
 100         struct CtdlSessData *ptr;
 101
 102         begin_critical_section(S_SESSION_TABLE);
 103         while (con->FirstSessData != NULL) {
 104                 lprintf(9, "Deallocating user data symbol %ld\n",
 105                         con->FirstSessData->sym_id);
 106                 if (con->FirstSessData->sym_data != NULL)
 107                         phree(con->FirstSessData->sym_data);
 108                 ptr = con->FirstSessData->next;
 109                 phree(con->FirstSessData);
 110                 con->FirstSessData = ptr;
 111         }
 112         end_critical_section(S_SESSION_TABLE);
 113 }
 114
 115
 116
 117
 118 /*
 119  * Gracefully terminate the session and thread.
 120  * (This is called as a cleanup handler by the thread library.)
 121  *
 122  * All NON-system-dependent stuff is done in this function.
 123  * System-dependent session/thread cleanup is in cleanup() in sysdep.c
 124  */
 125 void cleanup_stuff(void *arg)
 126 {
 127
 128         lprintf(9, "cleanup_stuff() called\n");
 129
 130         lprintf(7, "Calling logout(%d)\n", CC->cs_pid);
 131         logout(CC);
 132
 133         rec_log(CL_TERMINATE,CC->curr_user);
 134         unlink(CC->temp);
 135         lprintf(3, "citserver[%3d]: ended.\n",CC->cs_pid);
 136
 137         /* Run any cleanup routines registered by loadable modules */
 138         PerformSessionHooks(EVT_STOP);
 139
 140         syslog(LOG_NOTICE,"session %d ended", CC->cs_pid);
 141
 142         /* Deallocate any user-data attached to this session */
 143         deallocate_user_data(CC);
 144
 145         /* Now get rid of the session and context */
 146         lprintf(7, "cleanup_stuff() calling RemoveContext(%d)\n", CC->cs_pid);
 147         RemoveContext(CC);
 148
 149         /* While we still have an extra thread with no user attached to it,
 150          * take the opportunity to do some housekeeping before exiting.
 151          */
 152         do_housekeeping();
 153         }
 154
 155
 156 /*
 157  * Get a dynamic symbol number for per-session user data.
 158  * This API call should be made only ONCE per symbol per citserver run.
 159  */
 160 int CtdlGetDynamicSymbol()
 161 {
 162         static unsigned int next_symbol = SYM_MAX;
 163         return ++next_symbol;
 164 }
 165
 166
 167
 168 /*
 169  * Return a pointer to some generic per-session user data.
 170  * (This function returns NULL if the requested symbol is not allocated.)
 171  *
 172  * NOTE: we use critical sections for allocating and de-allocating these,
 173  *       but not for locating one.
 174  */
 175 void *CtdlGetUserData(unsigned long requested_sym)
 176 {
 177         struct CtdlSessData *ptr;
 178
 179         for (ptr = CC->FirstSessData; ptr != NULL; ptr = ptr->next)
 180                 if (ptr->sym_id == requested_sym)
 181                         return(ptr->sym_data);
 182
 183         lprintf(2, "ERROR! CtdlGetUserData(%ld) symbol not allocated\n",
 184                 requested_sym);
 185         return NULL;
 186 }
 187
 188
 189 /*
 190  * Allocate some generic per-session user data.
 191  */
 192 void CtdlAllocUserData(unsigned long requested_sym, size_t num_bytes)
 193 {
 194         struct CtdlSessData *ptr;
 195
 196         lprintf(9, "CtdlAllocUserData(%ld) called\n", requested_sym);
 197
 198         for (ptr = CC->FirstSessData; ptr != NULL; ptr = ptr->next)  {
 199                 if (ptr->sym_id == requested_sym) {
 200                         lprintf(2, "ERROR: CtdlAllocUserData() requested for"
 201                                 " symbol id %ld already registered\n",
 202                                 requested_sym);
 203                         return;
 204                 }
 205         }
 206
 207         ptr = mallok(sizeof(struct CtdlSessData));
 208         ptr->sym_id = requested_sym;
 209         ptr->sym_data = mallok(num_bytes);
 210
 211         begin_critical_section(S_SESSION_TABLE);
 212         ptr->next = CC->FirstSessData;
 213         CC->FirstSessData = ptr;
 214         end_critical_section(S_SESSION_TABLE);
 215
 216         lprintf(9, "CtdlAllocUserData(%ld) finished\n", requested_sym);
 217 }
 218
 219
 220
 221
 222
 223 /*
 224  * set_wtmpsupp()  -  alter the session listing
 225  */
 226 void set_wtmpsupp(char *newtext)
 227 {
 228         strncpy(CC->cs_room,newtext,sizeof CC->cs_room);
 229         CC->cs_room[sizeof CC->cs_room - 1] = 0;
 230         time(&CC->cs_lastupdt);
 231
 232         /* Run any routines registered by loadable modules */
 233         PerformSessionHooks(EVT_NEWROOM);
 234         }
 235
 236
 237 /*
 238  * call set_wtmpsupp() with the name of the current room, modified a bit...
 239  */
 240 void set_wtmpsupp_to_current_room() {
 241         if (CC->quickroom.QRflags & QR_PRIVATE) {
 242                 set_wtmpsupp("<private room>");
 243                 }
 244         else if (CC->quickroom.QRflags & QR_MAILBOX) {
 245                 set_wtmpsupp(&CC->quickroom.QRname[11]);
 246                 }
 247         else {
 248                 set_wtmpsupp(CC->quickroom.QRname);
 249                 }
 250         }
 251
 252
 253
 254 /*
 255  * cmd_info()  -  tell the client about this server
 256  */
 257 void cmd_info(void) {
 258         cprintf("%d Server info:\n",LISTING_FOLLOWS);
 259         cprintf("%d\n",CC->cs_pid);
 260         cprintf("%s\n",config.c_nodename);
 261         cprintf("%s\n",config.c_humannode);
 262         cprintf("%s\n",config.c_fqdn);
 263         cprintf("%s\n",CITADEL);
 264         cprintf("%d\n",REV_LEVEL);
 265         cprintf("%s\n",config.c_bbs_city);
 266         cprintf("%s\n",config.c_sysadm);
 267         cprintf("%d\n",SERVER_TYPE);
 268         cprintf("%s\n",config.c_moreprompt);
 269         cprintf("1\n"); /* 1 = yes, this system supports floors */
 270         cprintf("1\n"); /* 1 = we support the extended paging options */
 271         cprintf("000\n");
 272         }
 273
 274 void cmd_rchg(char *argbuf)
 275 {
 276         char newroomname[256]; /* set to 256 to prevent buffer overruns <dme>*/
 277
 278         extract(newroomname, argbuf, 0);
 279         newroomname[ROOMNAMELEN] = 0;
 280         if (strlen(newroomname) > 0) {
 281                 strncpy(CC->fake_roomname, newroomname, ROOMNAMELEN);
 282                 CC->fake_roomname[ROOMNAMELEN - 1] = 0;
 283                 }
 284         else {
 285                 strcpy(CC->fake_roomname, "");
 286                 }
 287         cprintf("%d OK\n", OK);
 288 }
 289
 290 void cmd_hchg(char *newhostname)
 291 {
 292    if ((newhostname) && (newhostname[0]))
 293    {
 294       memset(CC->fake_hostname, 0, 25);
 295       strncpy(CC->fake_hostname, newhostname, 24);
 296    }
 297    else
 298       strcpy(CC->fake_hostname, "");
 299    cprintf("%d OK\n",OK);
 300 }
 301
 302 void cmd_uchg(char *newusername)
 303 {
 304    if (CC->usersupp.axlevel < 6)
 305    {
 306       cprintf("%d You must be an Aide to use UCHG.\n",
 307                 ERROR+HIGHER_ACCESS_REQUIRED);
 308       return;
 309    }
 310    if ((newusername) && (newusername[0]))
 311    {
 312       CC->cs_flags &= ~CS_STEALTH;
 313       memset(CC->fake_username, 0, 32);
 314       if (strncasecmp(newusername, CC->curr_user, strlen(CC->curr_user)))
 315          strncpy(CC->fake_username, newusername, 31);
 316    }
 317    else
 318    {
 319       CC->fake_username[0] = '\0';
 320       CC->cs_flags |= CS_STEALTH;
 321    }
 322    cprintf("%d\n",OK);
 323 }
 324
 325 /*
 326  * returns an asterisk if there are any express messages waiting,
 327  * space otherwise.
 328  */
 329 char check_express(void) {
 330         if (CC->FirstExpressMessage == NULL) {
 331                 return(' ');
 332                 }
 333         else {
 334                 return('*');
 335                 }
 336         }
 337
 338 void cmd_time(void)
 339 {
 340    time_t tv;
 341
 342    tv = time(NULL);
 343
 344    cprintf("%d %ld\n", OK, tv);
 345 }
 346
 347 /*
 348  * Check whether two hostnames match.
 349  * "Realname" should be an actual name of a client that is trying to connect;
 350  * "testname" should be the value we are comparing it with. The idea is that we
 351  * want to compare with both the abbreviated and fully-qualified versions of
 352  * "testname;" some people define "localhost" as "localhost.foo.com," etc.
 353  */
 354 static int hostnames_match(const char *realname, const char *testname) {
 355         struct hostent *he;
 356         int retval = 0;
 357
 358         if (!strcasecmp(realname, testname))
 359                 return 1;
 360
 361 #ifdef HAVE_NONREENTRANT_NETDB
 362         begin_critical_section(S_NETDB);
 363 #endif
 364
 365         if ((he = gethostbyname(testname)) != NULL)
 366                 if (!strcasecmp(realname, he->h_name))
 367                         retval = 1;
 368
 369 #ifdef HAVE_NONREENTRANT_NETDB
 370         end_critical_section(S_NETDB);
 371 #endif
 372
 373         return retval;
 374         }
 375
 376 /*
 377  * check a hostname against the public_clients file
 378  */
 379 int is_public_client(char *where)
 380 {
 381         char buf[256];
 382         FILE *fp;
 383
 384         if (hostnames_match(where,"localhost")) return(1);
 385         if (hostnames_match(where,config.c_fqdn)) return(1);
 386
 387         fp = fopen("public_clients","r");
 388         if (fp == NULL) return(0);
 389
 390         while (fgets(buf,256,fp)!=NULL) {
 391                 while (isspace((buf[strlen(buf)-1])))
 392                         buf[strlen(buf)-1] = 0;
 393                 if (hostnames_match(where,buf)) {
 394                         fclose(fp);
 395                         return(1);
 396                         }
 397                 }
 398
 399         fclose(fp);
 400         return(0);
 401         }
 402
 403
 404 /*
 405  * the client is identifying itself to the server
 406  */
 407 void cmd_iden(char *argbuf)
 408 {
 409         int dev_code;
 410         int cli_code;
 411         int rev_level;
 412         char desc[256];
 413         char from_host[256];
 414         struct in_addr addr;
 415
 416         if (num_parms(argbuf)<4) {
 417                 cprintf("%d usage error\n",ERROR);
 418                 return;
 419                 }
 420
 421         dev_code = extract_int(argbuf,0);
 422         cli_code = extract_int(argbuf,1);
 423         rev_level = extract_int(argbuf,2);
 424         extract(desc,argbuf,3);
 425
 426         strncpy(from_host,config.c_fqdn,sizeof from_host);
 427         from_host[sizeof from_host - 1] = 0;
 428         if (num_parms(argbuf)>=5) extract(from_host,argbuf,4);
 429
 430         CC->cs_clientdev = dev_code;
 431         CC->cs_clienttyp = cli_code;
 432         CC->cs_clientver = rev_level;
 433         strncpy(CC->cs_clientname,desc,31);
 434         CC->cs_clientname[31] = 0;
 435
 436         if ((strlen(from_host)>0) &&
 437            (is_public_client(CC->cs_host))) {
 438                 if (inet_aton(from_host, &addr))
 439                         locate_host(CC->cs_host, &addr);
 440                 else {
 441                         strncpy(CC->cs_host,from_host,24);
 442                         CC->cs_host[24] = 0;
 443                         }
 444                 }
 445         set_wtmpsupp_to_current_room();
 446
 447         syslog(LOG_NOTICE,"client %d/%d/%01d.%02d (%s)\n",
 448                 dev_code,
 449                 cli_code,
 450                 (rev_level / 100),
 451                 (rev_level % 100),
 452                 desc);
 453                 cprintf("%d Ok\n",OK);
 454         }
 455
 456
 457 /*
 458  * enter or exit "stealth mode"
 459  */
 460 void cmd_stel(char *cmdbuf)
 461 {
 462         int requested_mode;
 463
 464         requested_mode = extract_int(cmdbuf,0);
 465         if (requested_mode !=0) requested_mode = 1;
 466
 467         if (!CC->logged_in) {
 468                 cprintf("%d Not logged in.\n",ERROR+NOT_LOGGED_IN);
 469                 return;
 470                 }
 471
 472         if (CC->usersupp.axlevel < 6) {
 473                 cprintf("%d You must be an Aide to use stealth mode.\n",
 474                         ERROR+HIGHER_ACCESS_REQUIRED);
 475                 return;
 476                 }
 477
 478         if (CC->cs_flags & CS_STEALTH) {
 479                 if (requested_mode == 0)
 480                         CC->cs_flags = CC->cs_flags-CS_STEALTH;
 481                 }
 482         else {
 483                 if (requested_mode == 1)
 484                         CC->cs_flags = CC->cs_flags|CS_STEALTH;
 485                 }
 486
 487         set_wtmpsupp_to_current_room();
 488         cprintf("%d Ok\n",OK);
 489         }
 490
 491
 492
 493
 494 /*
 495  * display system messages or help
 496  */
 497 void cmd_mesg(char *mname)
 498 {
 499         FILE *mfp;
 500         char targ[256];
 501         char buf[256];
 502         char *dirs[2];
 503
 504         extract(buf,mname,0);
 505
 506
 507         dirs[0]=mallok(64);
 508         dirs[1]=mallok(64);
 509         strcpy(dirs[0],"messages");
 510         strcpy(dirs[1],"help");
 511         mesg_locate(targ,buf,2,dirs);
 512         phree(dirs[0]);
 513         phree(dirs[1]);
 514
 515
 516         if (strlen(targ)==0) {
 517                 cprintf("%d '%s' not found.\n",ERROR,mname);
 518                 return;
 519                 }
 520
 521         mfp = fopen(targ,"r");
 522         if (mfp==NULL) {
 523                 cprintf("%d Cannot open '%s': %s\n",
 524                         ERROR,targ,strerror(errno));
 525                 return;
 526                 }
 527         cprintf("%d %s\n",LISTING_FOLLOWS,buf);
 528
 529         while (fgets(buf,255,mfp)!=NULL) {
 530                 buf[strlen(buf)-1] = 0;
 531                 do_help_subst(buf);
 532                 cprintf("%s\n",buf);
 533                 }
 534
 535         fclose(mfp);
 536         cprintf("000\n");
 537         }
 538
 539
 540 /*
 541  * enter system messages or help
 542  */
 543 void cmd_emsg(char *mname)
 544 {
 545         FILE *mfp;
 546         char targ[256];
 547         char buf[256];
 548         char *dirs[2];
 549         int a;
 550
 551         if (CC->usersupp.axlevel < 6) {
 552                 cprintf("%d You must be an Aide to edit system messages.\n",
 553                         ERROR+HIGHER_ACCESS_REQUIRED);
 554                 return;
 555                 }
 556
 557         extract(buf,mname,0);
 558         for (a=0; a<strlen(buf); ++a) {         /* security measure */
 559                 if (buf[a] == '/') buf[a] = '.';
 560                 }
 561
 562         dirs[0]=mallok(64);
 563         dirs[1]=mallok(64);
 564         strcpy(dirs[0],"messages");
 565         strcpy(dirs[1],"help");
 566         mesg_locate(targ,buf,2,dirs);
 567         phree(dirs[0]);
 568         phree(dirs[1]);
 569
 570         if (strlen(targ)==0) {
 571                 snprintf(targ, sizeof targ, "./help/%s", buf);
 572                 }
 573
 574         mfp = fopen(targ,"w");
 575         if (mfp==NULL) {
 576                 cprintf("%d Cannot open '%s': %s\n",
 577                         ERROR,targ,strerror(errno));
 578                 return;
 579                 }
 580         cprintf("%d %s\n", SEND_LISTING, targ);
 581
 582         while (client_gets(buf), strcmp(buf, "000")) {
 583                 fprintf(mfp, "%s\n", buf);
 584                 }
 585
 586         fclose(mfp);
 587         }
 588
 589
 590 /*
 591  * who's online
 592  */
 593 void cmd_rwho(void) {
 594         struct CitContext *cptr;
 595         int spoofed = 0;
 596         int aide;
 597         char un[40], room[40], host[40], flags[5];
 598
 599         aide = CC->usersupp.axlevel >= 6;
 600         cprintf("%d\n",LISTING_FOLLOWS);
 601
 602         for (cptr = ContextList; cptr != NULL; cptr = cptr->next)
 603         {
 604                 flags[0] = '\0';
 605                 spoofed = 0;
 606
 607                 if (cptr->cs_flags & CS_POSTING)
 608                    strcat(flags, "*");
 609                 else
 610                    strcat(flags, ".");
 611
 612                 if (cptr->fake_username[0])
 613                 {
 614                    strcpy(un, cptr->fake_username);
 615                    spoofed = 1;
 616                 }
 617                 else
 618                    strcpy(un, cptr->curr_user);
 619
 620                 if (cptr->fake_hostname[0])
 621                 {
 622                    strcpy(host, cptr->fake_hostname);
 623                    spoofed = 1;
 624                 }
 625                 else
 626                    strcpy(host, cptr->cs_host);
 627
 628                 if (cptr->fake_roomname[0])
 629                 {
 630                    strcpy(room, cptr->fake_roomname);
 631                    spoofed = 1;
 632                 }
 633                 else
 634                    strcpy(room, cptr->cs_room);
 635
 636
 637                 if ((aide) && (spoofed))
 638                    strcat(flags, "+");
 639
 640                 if ((cptr->cs_flags & CS_STEALTH) && (aide))
 641                    strcat(flags, "-");
 642
 643                 if (((cptr->cs_flags&CS_STEALTH)==0) || (aide))
 644                 {
 645                         cprintf("%d|%s|%s|%s|%s|%ld|%s|%s\n",
 646                                 cptr->cs_pid, un, room,
 647                                 host, cptr->cs_clientname,
 648                                 (long)(cptr->lastidle),
 649                                 cptr->lastcmdname, flags);
 650                 }
 651                 if ((spoofed) && (aide))
 652                 {
 653                         cprintf("%d|%s|%s|%s|%s|%ld|%s|%s\n",
 654                                 cptr->cs_pid, cptr->curr_user, cptr->cs_room,
 655                                 cptr->cs_host, cptr->cs_clientname,
 656                                 (long)(cptr->lastidle),
 657                                 cptr->lastcmdname, flags);
 658
 659                 }
 660         }
 661         cprintf("000\n");
 662         }
 663
 664
 665 /*
 666  * Terminate another running session
 667  */
 668 void cmd_term(char *cmdbuf)
 669 {
 670         int session_num;
 671         struct CitContext *ccptr;
 672         int session_to_kill = 0;
 673
 674         if (!CC->logged_in) {
 675                 cprintf("%d Not logged in.\n",ERROR+NOT_LOGGED_IN);
 676                 return;
 677                 }
 678
 679         if (CC->usersupp.axlevel < 6) {
 680                 cprintf("%d You must be an Aide to terminate sessions.\n",
 681                         ERROR+HIGHER_ACCESS_REQUIRED);
 682                 return;
 683                 }
 684
 685         session_num = extract_int(cmdbuf, 0);
 686         if (session_num == CC->cs_pid) {
 687                 cprintf("%d You can't kill your own session.\n", ERROR);
 688                 return;
 689                 }
 690
 691         lprintf(9, "Locating session to kill\n");
 692         begin_critical_section(S_SESSION_TABLE);
 693         for (ccptr = ContextList; ccptr != NULL; ccptr = ccptr->next) {
 694                 if (session_num == ccptr->cs_pid) {
 695                         session_to_kill = ccptr->cs_pid;
 696                         }
 697                 }
 698         end_critical_section(S_SESSION_TABLE);
 699         lprintf(9, "session_to_kill == %d\n", session_to_kill);
 700
 701         if (session_to_kill > 0) {
 702                 lprintf(9, "calling kill_session()\n");
 703                 kill_session(session_to_kill);
 704                 cprintf("%d Session terminated.\n", OK);
 705                 }
 706         else {
 707                 cprintf("%d No such session.\n", ERROR);
 708                 }
 709         }
 710
 711
 712
 713
 714
 715 /*
 716  * get the paginator prompt
 717  */
 718 void cmd_more(void) {
 719         cprintf("%d %s\n",OK,config.c_moreprompt);
 720         }
 721
 722 /*
 723  * echo
 724  */
 725 void cmd_echo(char *etext)
 726 {
 727         cprintf("%d %s\n",OK,etext);
 728         }
 729
 730
 731
 732 /*
 733  * identify as internal program
 734  */
 735 void cmd_ipgm(char *argbuf)
 736 {
 737         int secret;
 738
 739         secret = extract_int(argbuf, 0);
 740         if (secret == config.c_ipgm_secret) {
 741                 CC->internal_pgm = 1;
 742                 strcpy(CC->curr_user, "<internal program>");
 743                 CC->cs_flags = CC->cs_flags|CS_STEALTH;
 744                 cprintf("%d Authenticated as an internal program.\n",OK);
 745                 }
 746         else {
 747                 cprintf("%d Authentication failed.\n",ERROR);
 748                 }
 749         }
 750
 751
 752 /*
 753  * Shut down the server
 754  */
 755 void cmd_down(void) {
 756         if (!CC->logged_in) {
 757                 cprintf("%d Not logged in.\n",ERROR+NOT_LOGGED_IN);
 758                 return;
 759                 }
 760
 761         if (CC->usersupp.axlevel < 6) {
 762                 cprintf("%d You must be an Aide to shut down the server.\n",
 763                         ERROR+HIGHER_ACCESS_REQUIRED);
 764                 return;
 765                 }
 766
 767         cprintf("%d Shutting down server.  Goodbye.\n", OK);
 768         master_cleanup();
 769         }
 770
 771 /*
 772  * Schedule or cancel a server shutdown
 773  */
 774 void cmd_scdn(char *argbuf)
 775 {
 776         int new_state;
 777
 778         if (!CC->logged_in) {
 779                 cprintf("%d Not logged in.\n",ERROR+NOT_LOGGED_IN);
 780                 return;
 781                 }
 782
 783         if (CC->usersupp.axlevel < 6) {
 784                 cprintf("%d You must be an Aide to schedule a shutdown.\n",
 785                         ERROR+HIGHER_ACCESS_REQUIRED);
 786                 return;
 787                 }
 788
 789         new_state = extract_int(argbuf, 0);
 790         if ((new_state == 0) || (new_state == 1)) {
 791                 ScheduledShutdown = new_state;
 792                 }
 793         cprintf("%d %d\n", OK, ScheduledShutdown);
 794         }
 795
 796
 797 /*
 798  * main context loop
 799  */
 800 void *context_loop(struct CitContext *con)
 801 {
 802         char cmdbuf[256];
 803         int num_sessions, len;
 804         struct sockaddr_in sin;
 805
 806         /*
 807          * Wedge our way into the context table.
 808          */
 809         InitMyContext(con);
 810
 811         /*
 812          * Initialize some variables specific to our context.
 813          */
 814         CC->logged_in = 0;
 815         CC->internal_pgm = 0;
 816         CC->download_fp = NULL;
 817         CC->upload_fp = NULL;
 818         CC->cs_pid = con->client_socket;        /* not necessarily portable */
 819         CC->FirstExpressMessage = NULL;
 820         time(&CC->lastcmd);
 821         time(&CC->lastidle);
 822         strcpy(CC->lastcmdname, "    ");
 823         strcpy(CC->cs_clientname, "(unknown)");
 824         strcpy(CC->curr_user,"(not logged in)");
 825         strcpy(CC->net_node,"");
 826         snprintf(CC->temp, sizeof CC->temp, tmpnam(NULL));
 827         strcpy(CC->cs_room, "(no room)");
 828         strncpy(CC->cs_host, config.c_fqdn, sizeof CC->cs_host);
 829         CC->cs_host[sizeof CC->cs_host - 1] = 0;
 830         len = sizeof sin;
 831         if (!getpeername(CC->client_socket, (struct sockaddr *) &sin, &len))
 832                 locate_host(CC->cs_host, &sin.sin_addr);
 833         CC->cs_flags = 0;
 834         CC->upload_type = UPL_FILE;
 835         CC->dl_is_net = 0;
 836         CC->FirstSessData = NULL;
 837
 838         num_sessions = session_count();
 839         CC->nologin = 0;
 840         if ((config.c_maxsessions > 0)&&(num_sessions > config.c_maxsessions))
 841                 CC->nologin = 1;
 842
 843         if (CC->nologin==1) {
 844            cprintf("%d %s: Too many users are already online (maximum is %d)\n",
 845                 ERROR+MAX_SESSIONS_EXCEEDED,
 846                 config.c_nodename,config.c_maxsessions);
 847                 }
 848         else {
 849            cprintf("%d %s Citadel/UX server ready.\n",OK,config.c_nodename);
 850                 }
 851
 852         lprintf(3, "citserver[%3d]: started.\n", CC->cs_pid);
 853
 854         /* Run any session startup routines registered by loadable modules */
 855         PerformSessionHooks(EVT_START);
 856
 857         rec_log(CL_CONNECT, "");
 858
 859         do {
 860                 time(&CC->lastcmd);
 861                 memset(cmdbuf, 0, sizeof cmdbuf); /* Clear it, just in case */
 862                 if (client_gets(cmdbuf) < 1) cleanup(EXIT_NULL);
 863                 lprintf(5, "citserver[%3d]: %s\n", CC->cs_pid, cmdbuf);
 864
 865                 /*
 866                  * Let other clients see the last command we executed, and
 867                  * update the idle time, but not NOOP, PEXP, or GEXP.
 868                  */
 869                 if ( (strncasecmp(cmdbuf, "NOOP", 4))
 870                    && (strncasecmp(cmdbuf, "PEXP", 4))
 871                    && (strncasecmp(cmdbuf, "GEXP", 4)) ) {
 872                         strcpy(CC->lastcmdname, "    ");
 873                         strncpy(CC->lastcmdname, cmdbuf, 4);
 874                         time(&CC->lastidle);
 875                         }
 876
 877                 if ((strncasecmp(cmdbuf, "ENT0", 4)) && (strncasecmp(cmdbuf, "MESG", 4)) && (strncasecmp(cmdbuf, "MSGS", 4)))
 878                 {
 879                    CC->cs_flags &= ~CS_POSTING;
 880                 }
 881
 882 /*
 883  * This loop recognizes all server commands.
 884  */
 885
 886                 if (!strncasecmp(cmdbuf,"NOOP",4)) {
 887                         cprintf("%d%cok\n",OK,check_express());
 888                         }
 889
 890                 else if (!strncasecmp(cmdbuf,"QUIT",4)) {
 891                         cprintf("%d Goodbye.\n",OK);
 892                         }
 893
 894                 else if (!strncasecmp(cmdbuf,"LOUT",4)) {
 895                         if (CC->logged_in) logout(CC);
 896                         cprintf("%d logged out.\n",OK);
 897                         }
 898
 899                 else if (!strncasecmp(cmdbuf,"USER",4)) {
 900                         cmd_user(&cmdbuf[5]);
 901                         }
 902
 903                 else if (!strncasecmp(cmdbuf,"PASS",4)) {
 904                         cmd_pass(&cmdbuf[5]);
 905                         }
 906
 907                 else if (!strncasecmp(cmdbuf,"NEWU",4)) {
 908                         cmd_newu(&cmdbuf[5]);
 909                         }
 910
 911                 else if (!strncasecmp(cmdbuf,"SETP",4)) {
 912                         cmd_setp(&cmdbuf[5]);
 913                         }
 914
 915                 else if (!strncasecmp(cmdbuf,"LRMS",4)) {
 916                         cmd_lrms(&cmdbuf[5]);
 917                         }
 918
 919                 else if (!strncasecmp(cmdbuf,"LKRA",4)) {
 920                         cmd_lkra(&cmdbuf[5]);
 921                         }
 922
 923                 else if (!strncasecmp(cmdbuf,"LKRN",4)) {
 924                         cmd_lkrn(&cmdbuf[5]);
 925                         }
 926
 927                 else if (!strncasecmp(cmdbuf,"LKRO",4)) {
 928                         cmd_lkro(&cmdbuf[5]);
 929                         }
 930
 931                 else if (!strncasecmp(cmdbuf,"LZRM",4)) {
 932                         cmd_lzrm(&cmdbuf[5]);
 933                         }
 934
 935                 else if (!strncasecmp(cmdbuf,"GETU",4)) {
 936                         cmd_getu();
 937                         }
 938
 939                 else if (!strncasecmp(cmdbuf,"SETU",4)) {
 940                         cmd_setu(&cmdbuf[5]);
 941                         }
 942
 943                 else if (!strncasecmp(cmdbuf,"GOTO",4)) {
 944                         cmd_goto(&cmdbuf[5]);
 945                         }
 946
 947                 else if (!strncasecmp(cmdbuf,"MSGS",4)) {
 948                         cmd_msgs(&cmdbuf[5]);
 949                         }
 950
 951                 else if (!strncasecmp(cmdbuf,"WHOK",4)) {
 952                         cmd_whok();
 953                         }
 954
 955                 else if (!strncasecmp(cmdbuf,"RDIR",4)) {
 956                         cmd_rdir();
 957                         }
 958
 959                 else if (!strncasecmp(cmdbuf,"MSG0",4)) {
 960                         cmd_msg0(&cmdbuf[5]);
 961                         }
 962
 963                 else if (!strncasecmp(cmdbuf,"MSG2",4)) {
 964                         cmd_msg2(&cmdbuf[5]);
 965                         }
 966
 967                 else if (!strncasecmp(cmdbuf,"MSG3",4)) {
 968                         cmd_msg3(&cmdbuf[5]);
 969                         }
 970
 971                 else if (!strncasecmp(cmdbuf,"MSG4",4)) {
 972                         cmd_msg4(&cmdbuf[5]);
 973                         }
 974
 975                 else if (!strncasecmp(cmdbuf,"OPNA",4)) {
 976                         cmd_opna(&cmdbuf[5]);
 977                         }
 978
 979                 else if (!strncasecmp(cmdbuf,"INFO",4)) {
 980                         cmd_info();
 981                         }
 982
 983                 else if (!strncasecmp(cmdbuf,"SLRP",4)) {
 984                         cmd_slrp(&cmdbuf[5]);
 985                         }
 986
 987                 else if (!strncasecmp(cmdbuf,"INVT",4)) {
 988                         cmd_invt_kick(&cmdbuf[5],1);
 989                         }
 990
 991                 else if (!strncasecmp(cmdbuf,"KICK",4)) {
 992                         cmd_invt_kick(&cmdbuf[5],0);
 993                         }
 994
 995                 else if (!strncasecmp(cmdbuf,"GETR",4)) {
 996                         cmd_getr();
 997                         }
 998
 999                 else if (!strncasecmp(cmdbuf,"SETR",4)) {
1000                         cmd_setr(&cmdbuf[5]);
1001                         }
1002
1003                 else if (!strncasecmp(cmdbuf,"GETA",4)) {
1004                         cmd_geta();
1005                         }
1006
1007                 else if (!strncasecmp(cmdbuf,"SETA",4)) {
1008                         cmd_seta(&cmdbuf[5]);
1009                         }
1010
1011                 else if (!strncasecmp(cmdbuf,"ENT0",4)) {
1012                         cmd_ent0(&cmdbuf[5]);
1013                         }
1014
1015                 else if (!strncasecmp(cmdbuf,"ENT3",4)) {
1016                         cmd_ent3(&cmdbuf[5]);
1017                         }
1018
1019                 else if (!strncasecmp(cmdbuf,"RINF",4)) {
1020                         cmd_rinf();
1021                         }
1022
1023                 else if (!strncasecmp(cmdbuf,"DELE",4)) {
1024                         cmd_dele(&cmdbuf[5]);
1025                         }
1026
1027                 else if (!strncasecmp(cmdbuf,"KILL",4)) {
1028                         cmd_kill(&cmdbuf[5]);
1029                         }
1030
1031                 else if (!strncasecmp(cmdbuf,"CRE8",4)) {
1032                         cmd_cre8(&cmdbuf[5]);
1033                         }
1034
1035                 else if (!strncasecmp(cmdbuf,"MOVE",4)) {
1036                         cmd_move(&cmdbuf[5]);
1037                         }
1038
1039                 else if (!strncasecmp(cmdbuf,"FORG",4)) {
1040                         cmd_forg();
1041                         }
1042
1043                 else if (!strncasecmp(cmdbuf,"MESG",4)) {
1044                         cmd_mesg(&cmdbuf[5]);
1045                         }
1046
1047                 else if (!strncasecmp(cmdbuf,"EMSG",4)) {
1048                         cmd_emsg(&cmdbuf[5]);
1049                         }
1050
1051                 else if (!strncasecmp(cmdbuf,"GNUR",4)) {
1052                         cmd_gnur();
1053                         }
1054
1055                 else if (!strncasecmp(cmdbuf,"GREG",4)) {
1056                         cmd_greg(&cmdbuf[5]);
1057                         }
1058
1059                 else if (!strncasecmp(cmdbuf,"VALI",4)) {
1060                         cmd_vali(&cmdbuf[5]);
1061                         }
1062
1063                 else if (!strncasecmp(cmdbuf,"EINF",4)) {
1064                         cmd_einf(&cmdbuf[5]);
1065                         }
1066
1067                 else if (!strncasecmp(cmdbuf,"LIST",4)) {
1068                         cmd_list();
1069                         }
1070
1071                 else if (!strncasecmp(cmdbuf,"REGI",4)) {
1072                         cmd_regi();
1073                         }
1074
1075                 else if (!strncasecmp(cmdbuf,"CHEK",4)) {
1076                         cmd_chek();
1077                         }
1078
1079                 else if (!strncasecmp(cmdbuf,"DELF",4)) {
1080                         cmd_delf(&cmdbuf[5]);
1081                         }
1082
1083                 else if (!strncasecmp(cmdbuf,"MOVF",4)) {
1084                         cmd_movf(&cmdbuf[5]);
1085                         }
1086
1087                 else if (!strncasecmp(cmdbuf,"NETF",4)) {
1088                         cmd_netf(&cmdbuf[5]);
1089                         }
1090
1091                 else if (!strncasecmp(cmdbuf,"RWHO",4)) {
1092                         cmd_rwho();
1093                         }
1094
1095                 else if (!strncasecmp(cmdbuf,"OPEN",4)) {
1096                         cmd_open(&cmdbuf[5]);
1097                         }
1098
1099                 else if (!strncasecmp(cmdbuf,"CLOS",4)) {
1100                         cmd_clos();
1101                         }
1102
1103                 else if (!strncasecmp(cmdbuf,"UOPN",4)) {
1104                         cmd_uopn(&cmdbuf[5]);
1105                         }
1106
1107                 else if (!strncasecmp(cmdbuf,"UCLS",4)) {
1108                         cmd_ucls(&cmdbuf[5]);
1109                         }
1110
1111                 else if (!strncasecmp(cmdbuf,"READ",4)) {
1112                         cmd_read(&cmdbuf[5]);
1113                         }
1114
1115                 else if (!strncasecmp(cmdbuf,"WRIT",4)) {
1116                         cmd_writ(&cmdbuf[5]);
1117                         }
1118
1119                 else if (!strncasecmp(cmdbuf,"QUSR",4)) {
1120                         cmd_qusr(&cmdbuf[5]);
1121                         }
1122
1123                 else if (!strncasecmp(cmdbuf,"ECHO",4)) {
1124                         cmd_echo(&cmdbuf[5]);
1125                         }
1126
1127                 else if (!strncasecmp(cmdbuf,"OIMG",4)) {
1128                         cmd_oimg(&cmdbuf[5]);
1129                         }
1130
1131                 else if (!strncasecmp(cmdbuf,"MORE",4)) {
1132                         cmd_more();
1133                         }
1134
1135                 else if (!strncasecmp(cmdbuf,"NETP",4)) {
1136                         cmd_netp(&cmdbuf[5]);
1137                         }
1138
1139                 else if (!strncasecmp(cmdbuf,"NDOP",4)) {
1140                         cmd_ndop(&cmdbuf[5]);
1141                         }
1142
1143                 else if (!strncasecmp(cmdbuf,"NUOP",4)) {
1144                         cmd_nuop(&cmdbuf[5]);
1145                         }
1146
1147                 else if (!strncasecmp(cmdbuf,"LFLR",4)) {
1148                         cmd_lflr();
1149                         }
1150
1151                 else if (!strncasecmp(cmdbuf,"CFLR",4)) {
1152                         cmd_cflr(&cmdbuf[5]);
1153                         }
1154
1155                 else if (!strncasecmp(cmdbuf,"KFLR",4)) {
1156                         cmd_kflr(&cmdbuf[5]);
1157                         }
1158
1159                 else if (!strncasecmp(cmdbuf,"EFLR",4)) {
1160                         cmd_eflr(&cmdbuf[5]);
1161                         }
1162
1163                 else if (!strncasecmp(cmdbuf,"IDEN",4)) {
1164                         cmd_iden(&cmdbuf[5]);
1165                         }
1166
1167                 else if (!strncasecmp(cmdbuf,"IPGM",4)) {
1168                         cmd_ipgm(&cmdbuf[5]);
1169                         }
1170
1171                 else if (!strncasecmp(cmdbuf,"EBIO",4)) {
1172                         cmd_ebio();
1173                         }
1174
1175                 else if (!strncasecmp(cmdbuf,"RBIO",4)) {
1176                         cmd_rbio(&cmdbuf[5]);
1177                         }
1178
1179                 else if (!strncasecmp(cmdbuf,"LBIO",4)) {
1180                         cmd_lbio();
1181                         }
1182
1183                 else if (!strncasecmp(cmdbuf,"STEL",4)) {
1184                         cmd_stel(&cmdbuf[5]);
1185                         }
1186
1187                 else if (!strncasecmp(cmdbuf,"TERM",4)) {
1188                         cmd_term(&cmdbuf[5]);
1189                         }
1190
1191                 else if (!strncasecmp(cmdbuf,"DOWN",4)) {
1192                         cmd_down();
1193                         }
1194
1195                 else if (!strncasecmp(cmdbuf,"SCDN",4)) {
1196                         cmd_scdn(&cmdbuf[5]);
1197                         }
1198
1199                 else if (!strncasecmp(cmdbuf, "NSET", 4)) {
1200                         cmd_nset(&cmdbuf[5]);
1201                         }
1202
1203                 else if (!strncasecmp(cmdbuf, "UIMG", 4)) {
1204                         cmd_uimg(&cmdbuf[5]);
1205                         }
1206
1207                 else if (!strncasecmp(cmdbuf, "UCHG", 4)) {
1208                         cmd_uchg(&cmdbuf[5]);
1209                         }
1210
1211                 else if (!strncasecmp(cmdbuf, "TIME", 4)) {
1212                         cmd_time();
1213                         }
1214
1215                 else if (!strncasecmp(cmdbuf, "HCHG", 4)) {
1216                         cmd_hchg(&cmdbuf[5]);
1217                         }
1218
1219                 else if (!strncasecmp(cmdbuf, "RCHG", 4)) {
1220                         cmd_rchg(&cmdbuf[5]);
1221                         }
1222
1223                 else if (!strncasecmp(cmdbuf, "AGUP", 4)) {
1224                         cmd_agup(&cmdbuf[5]);
1225                         }
1226
1227                 else if (!strncasecmp(cmdbuf, "ASUP", 4)) {
1228                         cmd_asup(&cmdbuf[5]);
1229                         }
1230
1231                 else if (!strncasecmp(cmdbuf, "GPEX", 4)) {
1232                         cmd_gpex(&cmdbuf[5]);
1233                         }
1234
1235                 else if (!strncasecmp(cmdbuf, "SPEX", 4)) {
1236                         cmd_spex(&cmdbuf[5]);
1237                         }
1238
1239                 else if (!strncasecmp(cmdbuf, "CONF", 4)) {
1240                         cmd_conf(&cmdbuf[5]);
1241                         }
1242
1243 #ifdef DEBUG_MEMORY_LEAKS
1244                 else if (!strncasecmp(cmdbuf, "LEAK", 4)) {
1245                         dump_tracked();
1246                         }
1247 #endif
1248
1249                 else if (!DLoader_Exec_Cmd(cmdbuf))
1250                         {
1251                            cprintf("%d Unrecognized or unsupported command.\n",
1252                                     ERROR);
1253                         }
1254
1255                 /* Run any after-each-command outines registered by modules */
1256                 PerformSessionHooks(EVT_CMD);
1257
1258                 } while(strncasecmp(cmdbuf, "QUIT", 4));
1259
1260         cleanup(EXIT_NORMAL);
1261         return(NULL);
1262         }