citadel/citserver.c

   1 /*
   2  * $Id$
   3  *
   4  * Main source module for the Citadel server
   5  *
   6  */
   7
   8 #ifdef DLL_EXPORT
   9 #define IN_LIBCIT
  10 #endif
  11
  12 #include "sysdep.h"
  13 #include <stdlib.h>
  14 #include <unistd.h>
  15 #include <stdio.h>
  16 #include <fcntl.h>
  17 #include <signal.h>
  18
  19 #if TIME_WITH_SYS_TIME
  20 # include <sys/time.h>
  21 # include <time.h>
  22 #else
  23 # if HAVE_SYS_TIME_H
  24 #  include <sys/time.h>
  25 # else
  26 #  include <time.h>
  27 # endif
  28 #endif
  29
  30 #include <ctype.h>
  31 #include <string.h>
  32 #include <errno.h>
  33 #include <limits.h>
  34 #include <syslog.h>
  35 /* #include <dlfcn.h> */
  36 #include <netdb.h>
  37 #include <sys/types.h>
  38 #include <sys/socket.h>
  39 #include <netinet/in.h>
  40 #include <arpa/inet.h>
  41 #include "citadel.h"
  42 #include "server.h"
  43 #include "dynloader.h"
  44 #include "sysdep_decls.h"
  45 #include "citserver.h"
  46 #include "config.h"
  47 #include "database.h"
  48 #include "housekeeping.h"
  49 #include "user_ops.h"
  50 #include "logging.h"
  51 #include "msgbase.h"
  52 #include "support.h"
  53 #include "locate_host.h"
  54 #include "room_ops.h"
  55 #include "file_ops.h"
  56 #include "policy.h"
  57 #include "control.h"
  58 #include "tools.h"
  59
  60 #ifndef HAVE_SNPRINTF
  61 #include "snprintf.h"
  62 #endif
  63
  64 struct CitContext *ContextList = NULL;
  65 char *unique_session_numbers;
  66 int ScheduledShutdown = 0;
  67 int do_defrag = 0;
  68
  69 /*
  70  * Various things that need to be initialized at startup
  71  */
  72 void master_startup(void) {
  73         struct timeval tv;
  74
  75         lprintf(9, "master_startup() started\n");
  76         lprintf(7, "Opening databases\n");
  77         open_databases();
  78
  79         if (do_defrag) {
  80                 defrag_databases();
  81         }
  82
  83         check_ref_counts();
  84
  85         lprintf(7, "Creating base rooms (if necessary)\n");
  86         create_room(BASEROOM,           0, "", 0, 1, 0);
  87         create_room(AIDEROOM,           3, "", 0, 1, 0);
  88         create_room(SYSCONFIGROOM,      3, "", 0, 1, 0);
  89         create_room(config.c_twitroom,  0, "", 0, 1, 0);
  90
  91         lprintf(7, "Seeding the pseudo-random number generator...\n");
  92         gettimeofday(&tv, NULL);
  93         srand(tv.tv_usec);
  94         lprintf(9, "master_startup() finished\n");
  95 }
  96
  97
  98
  99 /*
 100  * Cleanup routine to be called when the server is shutting down.
 101  * WARNING: It's no longer safe to call this function to force a shutdown.
 102  * Instead, set time_to_die = 1.
 103  */
 104 void master_cleanup(void) {
 105         struct CleanupFunctionHook *fcn;
 106
 107         /* Run any cleanup routines registered by loadable modules */
 108         for (fcn = CleanupHookTable; fcn != NULL; fcn = fcn->next) {
 109                 (*fcn->h_function_pointer)();
 110         }
 111
 112         /* Close databases */
 113         lprintf(7, "Closing databases\n");
 114         close_databases();
 115
 116         /* Do system-dependent stuff */
 117         sysdep_master_cleanup();
 118
 119         /* Now go away. */
 120         lprintf(3, "citserver: exiting.\n");
 121         fflush(stdout); fflush(stderr);
 122         exit(0);
 123 }
 124
 125
 126 /*
 127  * Free any per-session data allocated by modules or whatever
 128  */
 129 void deallocate_user_data(struct CitContext *con)
 130 {
 131         struct CtdlSessData *ptr;
 132
 133         begin_critical_section(S_SESSION_TABLE);
 134         while (con->FirstSessData != NULL) {
 135                 lprintf(9, "Deallocating user data symbol %ld\n",
 136                         con->FirstSessData->sym_id);
 137                 if (con->FirstSessData->sym_data != NULL)
 138                         phree(con->FirstSessData->sym_data);
 139                 ptr = con->FirstSessData->next;
 140                 phree(con->FirstSessData);
 141                 con->FirstSessData = ptr;
 142         }
 143         end_critical_section(S_SESSION_TABLE);
 144 }
 145
 146
 147
 148
 149 /*
 150  * Terminate a session and remove its context data structure.
 151  */
 152 void RemoveContext (struct CitContext *con)
 153 {
 154         struct CitContext *ptr = NULL;
 155         struct CitContext *ToFree = NULL;
 156
 157         lprintf(9, "RemoveContext() called\n");
 158         if (con==NULL) {
 159                 lprintf(5, "WARNING: RemoveContext() called with NULL!\n");
 160                 return;
 161         }
 162
 163         /* Remove the context from the global context list.  This needs
 164          * to get done FIRST to avoid concurrency problems.  It is *vitally*
 165          * important to keep num_sessions accurate!!
 166          */
 167         lprintf(7, "Removing context for session %d\n", con->cs_pid);
 168         begin_critical_section(S_SESSION_TABLE);
 169         if (ContextList == con) {
 170                 ToFree = ContextList;
 171                 ContextList = ContextList->next;
 172                 --num_sessions;
 173         }
 174         else {
 175                 for (ptr = ContextList; ptr != NULL; ptr = ptr->next) {
 176                         if (ptr->next == con) {
 177                                 ToFree = ptr->next;
 178                                 ptr->next = ptr->next->next;
 179                                 --num_sessions;
 180                         }
 181                 }
 182         }
 183         end_critical_section(S_SESSION_TABLE);
 184
 185         if (ToFree == NULL) {
 186                 lprintf(9, "RemoveContext() found nothing to remove\n");
 187                 return;
 188         }
 189
 190         /* Run any cleanup routines registered by loadable modules.
 191          * Note 1: This must occur *before* deallocate_user_data() because the
 192          *         cleanup functions might touch dynamic session data.
 193          * Note 2: We have to "become_session()" because the cleanup functions
 194          *         might make references to "CC" assuming it's the right one.
 195          */
 196         become_session(con);
 197         PerformSessionHooks(EVT_STOP);
 198         become_session(NULL);
 199
 200         /* Now handle all of the administrivia. */
 201         lprintf(7, "Calling logout(%d)\n", con->cs_pid);
 202         logout(con);
 203
 204         rec_log(CL_TERMINATE, con->curr_user);
 205         unlink(con->temp);
 206         lprintf(3, "[%3d] Session ended.\n", con->cs_pid);
 207
 208
 209         syslog(LOG_NOTICE,"session %d: ended", con->cs_pid);
 210
 211         /* Deallocate any user-data attached to this session */
 212         deallocate_user_data(con);
 213
 214         /* If the client is still connected, blow 'em away. */
 215         lprintf(7, "Closing socket %d\n", con->client_socket);
 216         close(con->client_socket);
 217
 218         /* This is where we used to check for scheduled shutdowns. */
 219
 220         /* Free up the memory used by this context */
 221         phree(con);
 222
 223         lprintf(7, "Done with RemoveContext()\n");
 224 }
 225
 226
 227
 228 /*
 229  * Get a dynamic symbol number for per-session user data.
 230  * This API call should be made only ONCE per symbol per citserver run.
 231  */
 232 int CtdlGetDynamicSymbol()
 233 {
 234         static unsigned int next_symbol = SYM_MAX;
 235         return ++next_symbol;
 236 }
 237
 238
 239
 240 /*
 241  * Return a pointer to some generic per-session user data.
 242  * (This function returns NULL if the requested symbol is not allocated.)
 243  *
 244  * NOTE: we use critical sections for allocating and de-allocating these,
 245  *       but not for locating one.
 246  */
 247 void *CtdlGetUserData(unsigned long requested_sym)
 248 {
 249         struct CtdlSessData *ptr;
 250
 251         for (ptr = CC->FirstSessData; ptr != NULL; ptr = ptr->next)
 252                 if (ptr->sym_id == requested_sym)
 253                         return(ptr->sym_data);
 254
 255         lprintf(2, "ERROR! CtdlGetUserData(%ld) symbol not allocated\n",
 256                 requested_sym);
 257         return NULL;
 258 }
 259
 260
 261 /*
 262  * Allocate some generic per-session user data.
 263  */
 264 void CtdlAllocUserData(unsigned long requested_sym, size_t num_bytes)
 265 {
 266         struct CtdlSessData *ptr;
 267
 268         lprintf(9, "CtdlAllocUserData(%ld) called\n", requested_sym);
 269
 270         /* Fail silently if the symbol is already registered. */
 271         for (ptr = CC->FirstSessData; ptr != NULL; ptr = ptr->next)  {
 272                 if (ptr->sym_id == requested_sym) {
 273                         return;
 274                 }
 275         }
 276
 277         /* Grab us some memory!  Dem's good eatin' !!  */
 278         ptr = mallok(sizeof(struct CtdlSessData));
 279         ptr->sym_id = requested_sym;
 280         ptr->sym_data = mallok(num_bytes);
 281         memset(ptr->sym_data, 0, num_bytes);
 282
 283         begin_critical_section(S_SESSION_TABLE);
 284         ptr->next = CC->FirstSessData;
 285         CC->FirstSessData = ptr;
 286         end_critical_section(S_SESSION_TABLE);
 287
 288         lprintf(9, "CtdlAllocUserData(%ld) finished\n", requested_sym);
 289 }
 290
 291
 292 /*
 293  * Change the size of a buffer allocated with CtdlAllocUserData()
 294  */
 295 void CtdlReallocUserData(unsigned long requested_sym, size_t num_bytes)
 296 {
 297         struct CtdlSessData *ptr;
 298
 299         for (ptr = CC->FirstSessData; ptr != NULL; ptr = ptr->next)  {
 300                 if (ptr->sym_id == requested_sym) {
 301                         ptr->sym_data = reallok(ptr->sym_data, num_bytes);
 302                         return;
 303                 }
 304         }
 305
 306         lprintf(2, "CtdlReallocUserData() ERROR: symbol %ld not found!\n",
 307                 requested_sym);
 308 }
 309
 310
 311
 312
 313
 314
 315 /*
 316  * cmd_info()  -  tell the client about this server
 317  */
 318 void cmd_info(void) {
 319         cprintf("%d Server info:\n", LISTING_FOLLOWS);
 320         cprintf("%d\n", CC->cs_pid);
 321         cprintf("%s\n", config.c_nodename);
 322         cprintf("%s\n", config.c_humannode);
 323         cprintf("%s\n", config.c_fqdn);
 324         cprintf("%s\n", CITADEL);
 325         cprintf("%d\n", REV_LEVEL);
 326         cprintf("%s\n", config.c_bbs_city);
 327         cprintf("%s\n", config.c_sysadm);
 328         cprintf("%d\n", SERVER_TYPE);
 329         cprintf("%s\n", config.c_moreprompt);
 330         cprintf("1\n"); /* 1 = yes, this system supports floors */
 331         cprintf("1\n"); /* 1 = we support the extended paging options */
 332         cprintf("%s\n", CC->cs_nonce);
 333         cprintf("000\n");
 334 }
 335
 336
 337 /*
 338  * returns an asterisk if there are any express messages waiting,
 339  * space otherwise.
 340  */
 341 char CtdlCheckExpress(void) {
 342         if (CC->FirstExpressMessage == NULL) {
 343                 return(' ');
 344         }
 345         else {
 346                 return('*');
 347         }
 348 }
 349
 350 void cmd_time(void)
 351 {
 352    time_t tv;
 353    struct tm *tmp;
 354
 355    tv = time(NULL);
 356    tmp = localtime(&tv);
 357
 358    /* timezone and daylight global variables are not portable. */
 359 #ifdef HAVE_STRUCT_TM_TM_GMTOFF
 360    cprintf("%d %ld|%ld|%d\n", CIT_OK, (long)tv, tmp->tm_gmtoff, tmp->tm_isdst);
 361 #else
 362    cprintf("%d %ld|%ld|%d\n", CIT_OK, (long)tv, timezone, tmp->tm_isdst);
 363 #endif
 364 }
 365
 366 /*
 367  * Check whether two hostnames match.
 368  * "Realname" should be an actual name of a client that is trying to connect;
 369  * "testname" should be the value we are comparing it with. The idea is that we
 370  * want to compare with both the abbreviated and fully-qualified versions of
 371  * "testname;" some people define "localhost" as "localhost.foo.com," etc.
 372  */
 373 static int hostnames_match(const char *realname, const char *testname) {
 374         struct hostent *he;
 375         int retval = 0;
 376
 377         if (!strcasecmp(realname, testname)) {
 378                 return(1);
 379         }
 380
 381 #ifdef HAVE_NONREENTRANT_NETDB
 382         begin_critical_section(S_NETDB);
 383 #endif
 384
 385         if ((he = gethostbyname(testname)) != NULL) {
 386                 if (!strcasecmp(realname, he->h_name)) {
 387                         retval = 1;
 388                 }
 389         }
 390
 391 #ifdef HAVE_NONREENTRANT_NETDB
 392         end_critical_section(S_NETDB);
 393 #endif
 394
 395         return retval;
 396 }
 397
 398 /*
 399  * check a hostname against the public_clients file
 400  */
 401 int is_public_client(char *where)
 402 {
 403         char buf[SIZ];
 404         FILE *fp;
 405
 406         lprintf(9, "Checking whether %s is a public client\n", where);
 407
 408         if (hostnames_match(where, "localhost")) return(1);
 409         if (hostnames_match(where, config.c_fqdn)) return(1);
 410
 411         fp = fopen("public_clients","r");
 412         if (fp == NULL) return(0);
 413
 414         while (fgets(buf, sizeof buf, fp)!=NULL) {
 415                 while (isspace((buf[strlen(buf)-1])))
 416                         buf[strlen(buf)-1] = 0;
 417                 if (hostnames_match(where,buf)) {
 418                         fclose(fp);
 419                         return(1);
 420                 }
 421         }
 422
 423         fclose(fp);
 424         return(0);
 425 }
 426
 427
 428 /*
 429  * the client is identifying itself to the server
 430  */
 431 void cmd_iden(char *argbuf)
 432 {
 433         int dev_code;
 434         int cli_code;
 435         int rev_level;
 436         char desc[SIZ];
 437         char from_host[SIZ];
 438         struct in_addr addr;
 439         int do_lookup = 0;
 440
 441         if (num_parms(argbuf)<4) {
 442                 cprintf("%d usage error\n",ERROR);
 443                 return;
 444         }
 445
 446         dev_code = extract_int(argbuf,0);
 447         cli_code = extract_int(argbuf,1);
 448         rev_level = extract_int(argbuf,2);
 449         extract(desc,argbuf,3);
 450
 451         safestrncpy(from_host, config.c_fqdn, sizeof from_host);
 452         from_host[sizeof from_host - 1] = 0;
 453         if (num_parms(argbuf)>=5) extract(from_host,argbuf,4);
 454
 455         CC->cs_clientdev = dev_code;
 456         CC->cs_clienttyp = cli_code;
 457         CC->cs_clientver = rev_level;
 458         safestrncpy(CC->cs_clientname, desc, sizeof CC->cs_clientname);
 459         CC->cs_clientname[31] = 0;
 460
 461         if (strlen(from_host) > 0) {
 462                 if (CC->is_local_socket) do_lookup = 1;
 463                 else if (is_public_client(CC->cs_host)) do_lookup = 1;
 464         }
 465
 466         if (do_lookup) {
 467                 lprintf(9, "Looking up hostname '%s'\n", from_host);
 468                 if ((addr.s_addr = inet_addr(from_host)) != -1) {
 469                         locate_host(CC->cs_host, sizeof CC->cs_host, &addr);
 470                 }
 471                 else {
 472                         safestrncpy(CC->cs_host, from_host, sizeof CC->cs_host);
 473                         CC->cs_host[sizeof CC->cs_host - 1] = 0;
 474                 }
 475         }
 476
 477         lprintf(7, "client %d/%d/%01d.%02d (%s)\n",
 478                 dev_code,
 479                 cli_code,
 480                 (rev_level / 100),
 481                 (rev_level % 100),
 482                 desc);
 483
 484         syslog(LOG_NOTICE,"session %d: client %d/%d/%01d.%02d (%s) from %s\n",
 485                 CC->cs_pid,
 486                 dev_code,
 487                 cli_code,
 488                 (rev_level / 100),
 489                 (rev_level % 100),
 490                 desc,
 491                 CC->cs_host);
 492         cprintf("%d Ok\n",CIT_OK);
 493 }
 494
 495
 496 /*
 497  * display system messages or help
 498  */
 499 void cmd_mesg(char *mname)
 500 {
 501         FILE *mfp;
 502         char targ[SIZ];
 503         char buf[SIZ];
 504         char *dirs[2];
 505
 506         extract(buf,mname,0);
 507
 508
 509         dirs[0]=mallok(64);
 510         dirs[1]=mallok(64);
 511         strcpy(dirs[0],"messages");
 512         strcpy(dirs[1],"help");
 513         mesg_locate(targ,sizeof targ,buf,2,(const char **)dirs);
 514         phree(dirs[0]);
 515         phree(dirs[1]);
 516
 517
 518         if (strlen(targ)==0) {
 519                 cprintf("%d '%s' not found.\n",ERROR,mname);
 520                 return;
 521         }
 522
 523         mfp = fopen(targ,"r");
 524         if (mfp==NULL) {
 525                 cprintf("%d Cannot open '%s': %s\n",
 526                         ERROR,targ,strerror(errno));
 527                 return;
 528         }
 529         cprintf("%d %s\n",LISTING_FOLLOWS,buf);
 530
 531         while (fgets(buf, (SIZ-1), mfp)!=NULL) {
 532                 buf[strlen(buf)-1] = 0;
 533                 do_help_subst(buf);
 534                 cprintf("%s\n",buf);
 535         }
 536
 537         fclose(mfp);
 538         cprintf("000\n");
 539 }
 540
 541
 542 /*
 543  * enter system messages or help
 544  */
 545 void cmd_emsg(char *mname)
 546 {
 547         FILE *mfp;
 548         char targ[SIZ];
 549         char buf[SIZ];
 550         char *dirs[2];
 551         int a;
 552
 553         if (CtdlAccessCheck(ac_aide)) return;
 554
 555         extract(buf,mname,0);
 556         for (a=0; a<strlen(buf); ++a) {         /* security measure */
 557                 if (buf[a] == '/') buf[a] = '.';
 558         }
 559
 560         dirs[0]=mallok(64);
 561         dirs[1]=mallok(64);
 562         strcpy(dirs[0],"messages");
 563         strcpy(dirs[1],"help");
 564         mesg_locate(targ,sizeof targ,buf,2,(const char**)dirs);
 565         phree(dirs[0]);
 566         phree(dirs[1]);
 567
 568         if (strlen(targ)==0) {
 569                 snprintf(targ, sizeof targ, "./help/%s", buf);
 570         }
 571
 572         mfp = fopen(targ,"w");
 573         if (mfp==NULL) {
 574                 cprintf("%d Cannot open '%s': %s\n",
 575                         ERROR,targ,strerror(errno));
 576                 return;
 577         }
 578         cprintf("%d %s\n", SEND_LISTING, targ);
 579
 580         while (client_gets(buf), strcmp(buf, "000")) {
 581                 fprintf(mfp, "%s\n", buf);
 582         }
 583
 584         fclose(mfp);
 585 }
 586
 587
 588 /* Don't show the names of private rooms unless the viewing
 589  * user also knows the rooms.
 590  */
 591 void GenerateRoomDisplay(char *real_room,
 592                         struct CitContext *viewed,
 593                         struct CitContext *viewer) {
 594
 595         strcpy(real_room, viewed->quickroom.QRname);
 596         if (viewed->quickroom.QRflags & QR_MAILBOX) {
 597                 strcpy(real_room, &real_room[11]);
 598         }
 599         if (viewed->quickroom.QRflags & QR_PRIVATE) {
 600                 if ( (CtdlRoomAccess(&viewed->quickroom, &viewer->usersupp)
 601                    & UA_KNOWN) == 0) {
 602                         strcpy(real_room, "<private room>");
 603                 }
 604         }
 605
 606         if (viewed->cs_flags & CS_CHAT) {
 607                 while (strlen(real_room) < 14)
 608                         strcat(real_room, " ");
 609
 610                 strcpy(&real_room[14], "<chat>");
 611         }
 612
 613 }
 614
 615 /*
 616  * Convenience function.
 617  */
 618 int CtdlAccessCheck(int required_level) {
 619
 620         if (CC->internal_pgm) return(0);
 621         if (required_level >= ac_internal) {
 622                 cprintf("%d This is not a user-level command.\n",
 623                         ERROR+HIGHER_ACCESS_REQUIRED);
 624                 return(-1);
 625         }
 626
 627         if (CC->usersupp.axlevel >= 6) return(0);
 628         if (required_level >= ac_aide) {
 629                 cprintf("%d This command requires Aide access.\n",
 630                         ERROR+HIGHER_ACCESS_REQUIRED);
 631                 return(-1);
 632         }
 633
 634         if (is_room_aide()) return(0);
 635         if (required_level >= ac_room_aide) {
 636                 cprintf("%d This command requires Aide or Room Aide access.\n",
 637                         ERROR + HIGHER_ACCESS_REQUIRED);
 638                 return(-1);
 639         }
 640
 641         if (CC->logged_in) return(0);
 642         if (required_level >= ac_logged_in) {
 643                 cprintf("%d Not logged in.\n", ERROR+NOT_LOGGED_IN);
 644                 return(-1);
 645         }
 646
 647         /* shhh ... succeed quietly */
 648         return(0);
 649 }
 650
 651
 652
 653 /*
 654  * Terminate another running session
 655  */
 656 void cmd_term(char *cmdbuf)
 657 {
 658         int session_num;
 659         struct CitContext *ccptr;
 660         int found_it = 0;
 661         int allowed = 0;
 662
 663         session_num = extract_int(cmdbuf, 0);
 664         if (session_num == CC->cs_pid) {
 665                 cprintf("%d You can't kill your own session.\n", ERROR);
 666                 return;
 667         }
 668
 669         lprintf(9, "Locating session to kill\n");
 670         begin_critical_section(S_SESSION_TABLE);
 671         for (ccptr = ContextList; ccptr != NULL; ccptr = ccptr->next) {
 672                 if (session_num == ccptr->cs_pid) {
 673                         found_it = 1;
 674                         if ((ccptr->usersupp.usernum == CC->usersupp.usernum)
 675                            || (CC->usersupp.axlevel >= 6)) {
 676                                 allowed = 1;
 677                                 ccptr->kill_me = 1;
 678                         }
 679                         else {
 680                                 allowed = 0;
 681                         }
 682                 }
 683         }
 684         end_critical_section(S_SESSION_TABLE);
 685
 686         if (found_it) {
 687                 if (allowed) {
 688                         cprintf("%d Session terminated.\n", CIT_OK);
 689                 }
 690                 else {
 691                         cprintf("%d You are not allowed to do that.\n",
 692                                 ERROR + HIGHER_ACCESS_REQUIRED);
 693                 }
 694         }
 695         else {
 696                 cprintf("%d No such session.\n", ERROR);
 697         }
 698 }
 699
 700
 701
 702
 703
 704 /*
 705  * get the paginator prompt
 706  */
 707 void cmd_more(void) {
 708         cprintf("%d %s\n", CIT_OK, config.c_moreprompt);
 709 }
 710
 711 /*
 712  * echo
 713  */
 714 void cmd_echo(char *etext)
 715 {
 716         cprintf("%d %s\n", CIT_OK, etext);
 717 }
 718
 719
 720
 721 /*
 722  * identify as internal program
 723  */
 724 void cmd_ipgm(char *argbuf)
 725 {
 726         int secret;
 727
 728         secret = extract_int(argbuf, 0);
 729         if (secret == config.c_ipgm_secret) {
 730                 CC->internal_pgm = 1;
 731                 strcpy(CC->curr_user, "<internal program>");
 732                 CC->cs_flags = CC->cs_flags|CS_STEALTH;
 733                 cprintf("%d Authenticated as an internal program.\n",CIT_OK);
 734         }
 735         else {
 736                 cprintf("%d Authentication failed.\n",ERROR);
 737                 lprintf(3, "Warning: ipgm authentication failed.\n");
 738         }
 739 }
 740
 741
 742 /*
 743  * Shut down the server
 744  */
 745 void cmd_down(void) {
 746
 747         if (CtdlAccessCheck(ac_aide)) return;
 748
 749         cprintf("%d Shutting down server.  Goodbye.\n", CIT_OK);
 750         time_to_die = 1;
 751 }
 752
 753 /*
 754  * Schedule or cancel a server shutdown
 755  */
 756 void cmd_scdn(char *argbuf)
 757 {
 758         int new_state;
 759
 760         if (CtdlAccessCheck(ac_aide)) return;
 761
 762         new_state = extract_int(argbuf, 0);
 763         if ((new_state == 0) || (new_state == 1)) {
 764                 ScheduledShutdown = new_state;
 765         }
 766         cprintf("%d %d\n", CIT_OK, ScheduledShutdown);
 767 }
 768
 769
 770 /*
 771  * Set or unset asynchronous protocol mode
 772  */
 773 void cmd_asyn(char *argbuf)
 774 {
 775         int new_state;
 776
 777         new_state = extract_int(argbuf, 0);
 778         if ((new_state == 0) || (new_state == 1)) {
 779                 CC->is_async = new_state;
 780         }
 781         cprintf("%d %d\n", CIT_OK, CC->is_async);
 782 }
 783
 784
 785 /*
 786  * Generate a "nonce" for APOP-style authentication.
 787  *
 788  * RFC 1725 et al specify a PID to be placed in front of the nonce.
 789  * Quoth BTX: That would be stupid.
 790  */
 791 void generate_nonce(struct CitContext *con) {
 792         struct timeval tv;
 793
 794         memset(con->cs_nonce, NONCE_SIZE, 0);
 795         gettimeofday(&tv, NULL);
 796         memset(con->cs_nonce, NONCE_SIZE, 0);
 797         snprintf(con->cs_nonce, NONCE_SIZE, "<%d%ld@%s>",
 798                 rand(), (long)tv.tv_usec, config.c_fqdn);
 799 }
 800
 801
 802
 803
 804 /*
 805  * Back-end function for starting a session
 806  */
 807 void begin_session(struct CitContext *con)
 808 {
 809         int len;
 810         struct sockaddr_in sin;
 811
 812         /*
 813          * Initialize some variables specific to our context.
 814          */
 815         con->logged_in = 0;
 816         con->internal_pgm = 0;
 817         con->download_fp = NULL;
 818         con->upload_fp = NULL;
 819         con->FirstExpressMessage = NULL;
 820         time(&con->lastcmd);
 821         time(&con->lastidle);
 822         strcpy(con->lastcmdname, "    ");
 823         strcpy(con->cs_clientname, "(unknown)");
 824         strcpy(con->curr_user, NLI);
 825         strcpy(con->net_node,"");
 826         strcpy(con->fake_username, "");
 827         strcpy(con->fake_postname, "");
 828         strcpy(con->fake_hostname, "");
 829         strcpy(con->fake_roomname, "");
 830         generate_nonce(con);
 831         snprintf(con->temp, sizeof con->temp, tmpnam(NULL));
 832         safestrncpy(con->cs_host, config.c_fqdn, sizeof con->cs_host);
 833         con->cs_host[sizeof con->cs_host - 1] = 0;
 834         len = sizeof sin;
 835         if (!CC->is_local_socket) {
 836                 if (!getpeername(con->client_socket,
 837                    (struct sockaddr *) &sin, &len))
 838                         locate_host(con->cs_host, sizeof con->cs_host, &sin.sin_addr);
 839         }
 840         else {
 841                 strcpy(con->cs_host, "");
 842         }
 843         con->cs_flags = 0;
 844         con->upload_type = UPL_FILE;
 845         con->dl_is_net = 0;
 846         con->FirstSessData = NULL;
 847
 848         con->nologin = 0;
 849         if ((config.c_maxsessions > 0)&&(num_sessions > config.c_maxsessions))
 850                 con->nologin = 1;
 851
 852         lprintf(3, "Session started.\n");
 853
 854         /* Run any session startup routines registered by loadable modules */
 855         PerformSessionHooks(EVT_START);
 856
 857         rec_log(CL_CONNECT, "");
 858 }
 859
 860
 861 void citproto_begin_session() {
 862         if (CC->nologin==1) {
 863                 cprintf("%d %s: Too many users are already online "
 864                         "(maximum is %d)\n",
 865                         ERROR+MAX_SESSIONS_EXCEEDED,
 866                         config.c_nodename, config.c_maxsessions);
 867         }
 868         else {
 869                 cprintf("%d %s Citadel/UX server ready.\n",
 870                         CIT_OK, config.c_nodename);
 871         }
 872 }
 873
 874
 875
 876
 877 /*
 878  * This loop recognizes all server commands.
 879  */
 880 void do_command_loop(void) {
 881         char cmdbuf[SIZ];
 882
 883         time(&CC->lastcmd);
 884         memset(cmdbuf, 0, sizeof cmdbuf); /* Clear it, just in case */
 885         if (client_gets(cmdbuf) < 1) {
 886                 lprintf(3, "Client socket is broken.  Ending session.\n");
 887                 CC->kill_me = 1;
 888                 return;
 889         }
 890         lprintf(5, "Citadel: %s\n", cmdbuf);
 891
 892         /*
 893          * Let other clients see the last command we executed, and
 894          * update the idle time, but not NOOP, PEXP, or GEXP.
 895          */
 896         if ( (strncasecmp(cmdbuf, "NOOP", 4))
 897            && (strncasecmp(cmdbuf, "PEXP", 4))
 898            && (strncasecmp(cmdbuf, "GEXP", 4)) ) {
 899                 strcpy(CC->lastcmdname, "    ");
 900                 safestrncpy(CC->lastcmdname, cmdbuf,
 901                         sizeof(CC->lastcmdname) );
 902                 time(&CC->lastidle);
 903         }
 904
 905         if ((strncasecmp(cmdbuf, "ENT0", 4))
 906            && (strncasecmp(cmdbuf, "MESG", 4))
 907            && (strncasecmp(cmdbuf, "MSGS", 4)))
 908         {
 909            CC->cs_flags &= ~CS_POSTING;
 910         }
 911
 912         if (!strncasecmp(cmdbuf,"NOOP",4)) {
 913                 cprintf("%d%cok\n",CIT_OK,CtdlCheckExpress());
 914         }
 915
 916         else if (!strncasecmp(cmdbuf,"QUIT",4)) {
 917                 cprintf("%d Goodbye.\n",CIT_OK);
 918                 CC->kill_me = 1;
 919         }
 920
 921         else if (!strncasecmp(cmdbuf,"ASYN",4)) {
 922                 cmd_asyn(&cmdbuf[5]);
 923         }
 924
 925         else if (!strncasecmp(cmdbuf,"LOUT",4)) {
 926                 if (CC->logged_in) logout(CC);
 927                 cprintf("%d logged out.\n",CIT_OK);
 928         }
 929
 930         else if (!strncasecmp(cmdbuf,"USER",4)) {
 931                 cmd_user(&cmdbuf[5]);
 932         }
 933
 934         else if (!strncasecmp(cmdbuf,"PASS",4)) {
 935                 cmd_pass(&cmdbuf[5]);
 936         }
 937
 938         else if (!strncasecmp(cmdbuf,"NEWU",4)) {
 939                 cmd_newu(&cmdbuf[5]);
 940         }
 941
 942         else if (!strncasecmp(cmdbuf,"CREU",4)) {
 943                 cmd_creu(&cmdbuf[5]);
 944         }
 945
 946         else if (!strncasecmp(cmdbuf,"SETP",4)) {
 947                 cmd_setp(&cmdbuf[5]);
 948         }
 949
 950         else if (!strncasecmp(cmdbuf,"LRMS",4)) {
 951                 cmd_lrms(&cmdbuf[5]);
 952         }
 953
 954         else if (!strncasecmp(cmdbuf,"LKRA",4)) {
 955                 cmd_lkra(&cmdbuf[5]);
 956         }
 957
 958         else if (!strncasecmp(cmdbuf,"LKRN",4)) {
 959                 cmd_lkrn(&cmdbuf[5]);
 960         }
 961
 962         else if (!strncasecmp(cmdbuf,"LKRO",4)) {
 963                 cmd_lkro(&cmdbuf[5]);
 964         }
 965
 966         else if (!strncasecmp(cmdbuf,"LZRM",4)) {
 967                 cmd_lzrm(&cmdbuf[5]);
 968         }
 969
 970         else if (!strncasecmp(cmdbuf,"GETU",4)) {
 971                 cmd_getu();
 972         }
 973
 974         else if (!strncasecmp(cmdbuf,"SETU",4)) {
 975                 cmd_setu(&cmdbuf[5]);
 976         }
 977
 978         else if (!strncasecmp(cmdbuf,"GOTO",4)) {
 979                 cmd_goto(&cmdbuf[5]);
 980         }
 981
 982         else if (!strncasecmp(cmdbuf,"MSGS",4)) {
 983                 cmd_msgs(&cmdbuf[5]);
 984         }
 985
 986         else if (!strncasecmp(cmdbuf,"WHOK",4)) {
 987                 cmd_whok();
 988         }
 989
 990         else if (!strncasecmp(cmdbuf,"RDIR",4)) {
 991                 cmd_rdir();
 992         }
 993
 994         else if (!strncasecmp(cmdbuf,"MSG0",4)) {
 995                 cmd_msg0(&cmdbuf[5]);
 996         }
 997
 998         else if (!strncasecmp(cmdbuf,"MSG2",4)) {
 999                 cmd_msg2(&cmdbuf[5]);
1000         }
1001
1002         else if (!strncasecmp(cmdbuf,"MSG3",4)) {
1003                 cmd_msg3(&cmdbuf[5]);
1004         }
1005
1006         else if (!strncasecmp(cmdbuf,"MSG4",4)) {
1007                 cmd_msg4(&cmdbuf[5]);
1008         }
1009
1010         else if (!strncasecmp(cmdbuf,"OPNA",4)) {
1011                 cmd_opna(&cmdbuf[5]);
1012         }
1013
1014         else if (!strncasecmp(cmdbuf,"INFO",4)) {
1015                 cmd_info();
1016         }
1017
1018         else if (!strncasecmp(cmdbuf,"SLRP",4)) {
1019                 cmd_slrp(&cmdbuf[5]);
1020         }
1021
1022         else if (!strncasecmp(cmdbuf,"INVT",4)) {
1023                 cmd_invt_kick(&cmdbuf[5],1);
1024         }
1025
1026         else if (!strncasecmp(cmdbuf,"KICK",4)) {
1027                 cmd_invt_kick(&cmdbuf[5],0);
1028         }
1029
1030         else if (!strncasecmp(cmdbuf,"GETR",4)) {
1031                 cmd_getr();
1032         }
1033
1034         else if (!strncasecmp(cmdbuf,"SETR",4)) {
1035                 cmd_setr(&cmdbuf[5]);
1036         }
1037
1038         else if (!strncasecmp(cmdbuf,"GETA",4)) {
1039                 cmd_geta();
1040         }
1041
1042         else if (!strncasecmp(cmdbuf,"SETA",4)) {
1043                 cmd_seta(&cmdbuf[5]);
1044         }
1045
1046         else if (!strncasecmp(cmdbuf,"ENT0",4)) {
1047                 cmd_ent0(&cmdbuf[5]);
1048         }
1049
1050         else if (!strncasecmp(cmdbuf,"RINF",4)) {
1051                 cmd_rinf();
1052         }
1053
1054         else if (!strncasecmp(cmdbuf,"DELE",4)) {
1055                 cmd_dele(&cmdbuf[5]);
1056         }
1057
1058         else if (!strncasecmp(cmdbuf,"KILL",4)) {
1059                 cmd_kill(&cmdbuf[5]);
1060         }
1061
1062         else if (!strncasecmp(cmdbuf,"CRE8",4)) {
1063                 cmd_cre8(&cmdbuf[5]);
1064         }
1065
1066         else if (!strncasecmp(cmdbuf,"MOVE",4)) {
1067                 cmd_move(&cmdbuf[5]);
1068         }
1069
1070         else if (!strncasecmp(cmdbuf,"FORG",4)) {
1071                 cmd_forg();
1072         }
1073
1074         else if (!strncasecmp(cmdbuf,"MESG",4)) {
1075                 cmd_mesg(&cmdbuf[5]);
1076         }
1077
1078         else if (!strncasecmp(cmdbuf,"EMSG",4)) {
1079                 cmd_emsg(&cmdbuf[5]);
1080         }
1081
1082         else if (!strncasecmp(cmdbuf,"GNUR",4)) {
1083                 cmd_gnur();
1084         }
1085
1086         else if (!strncasecmp(cmdbuf,"VALI",4)) {
1087                 cmd_vali(&cmdbuf[5]);
1088         }
1089
1090         else if (!strncasecmp(cmdbuf,"EINF",4)) {
1091                 cmd_einf(&cmdbuf[5]);
1092         }
1093
1094         else if (!strncasecmp(cmdbuf,"LIST",4)) {
1095                 cmd_list();
1096         }
1097
1098         else if (!strncasecmp(cmdbuf,"CHEK",4)) {
1099                 cmd_chek();
1100         }
1101
1102         else if (!strncasecmp(cmdbuf,"DELF",4)) {
1103                 cmd_delf(&cmdbuf[5]);
1104         }
1105
1106         else if (!strncasecmp(cmdbuf,"MOVF",4)) {
1107                 cmd_movf(&cmdbuf[5]);
1108         }
1109
1110         else if (!strncasecmp(cmdbuf,"NETF",4)) {
1111                 cmd_netf(&cmdbuf[5]);
1112         }
1113
1114         else if (!strncasecmp(cmdbuf,"OPEN",4)) {
1115                 cmd_open(&cmdbuf[5]);
1116         }
1117
1118         else if (!strncasecmp(cmdbuf,"CLOS",4)) {
1119                 cmd_clos();
1120         }
1121
1122         else if (!strncasecmp(cmdbuf,"UOPN",4)) {
1123                 cmd_uopn(&cmdbuf[5]);
1124         }
1125
1126         else if (!strncasecmp(cmdbuf,"UCLS",4)) {
1127                 cmd_ucls(&cmdbuf[5]);
1128         }
1129
1130         else if (!strncasecmp(cmdbuf,"READ",4)) {
1131                 cmd_read(&cmdbuf[5]);
1132         }
1133
1134         else if (!strncasecmp(cmdbuf,"WRIT",4)) {
1135                 cmd_writ(&cmdbuf[5]);
1136         }
1137
1138         else if (!strncasecmp(cmdbuf,"QUSR",4)) {
1139                 cmd_qusr(&cmdbuf[5]);
1140         }
1141
1142         else if (!strncasecmp(cmdbuf,"ECHO",4)) {
1143                 cmd_echo(&cmdbuf[5]);
1144         }
1145
1146         else if (!strncasecmp(cmdbuf,"OIMG",4)) {
1147                 cmd_oimg(&cmdbuf[5]);
1148         }
1149
1150         else if (!strncasecmp(cmdbuf,"MORE",4)) {
1151                 cmd_more();
1152         }
1153
1154         else if (!strncasecmp(cmdbuf,"NDOP",4)) {
1155                 cmd_ndop(&cmdbuf[5]);
1156         }
1157
1158         else if (!strncasecmp(cmdbuf,"NUOP",4)) {
1159                 cmd_nuop(&cmdbuf[5]);
1160         }
1161
1162         else if (!strncasecmp(cmdbuf,"LFLR",4)) {
1163                 cmd_lflr();
1164         }
1165
1166         else if (!strncasecmp(cmdbuf,"CFLR",4)) {
1167                 cmd_cflr(&cmdbuf[5]);
1168         }
1169
1170         else if (!strncasecmp(cmdbuf,"KFLR",4)) {
1171                 cmd_kflr(&cmdbuf[5]);
1172         }
1173
1174         else if (!strncasecmp(cmdbuf,"EFLR",4)) {
1175                 cmd_eflr(&cmdbuf[5]);
1176         }
1177
1178         else if (!strncasecmp(cmdbuf,"IDEN",4)) {
1179                 cmd_iden(&cmdbuf[5]);
1180         }
1181
1182         else if (!strncasecmp(cmdbuf,"IPGM",4)) {
1183                 cmd_ipgm(&cmdbuf[5]);
1184         }
1185
1186         else if (!strncasecmp(cmdbuf,"TERM",4)) {
1187                 cmd_term(&cmdbuf[5]);
1188         }
1189
1190         else if (!strncasecmp(cmdbuf,"DOWN",4)) {
1191                 cmd_down();
1192         }
1193
1194         else if (!strncasecmp(cmdbuf,"SCDN",4)) {
1195                 cmd_scdn(&cmdbuf[5]);
1196         }
1197
1198         else if (!strncasecmp(cmdbuf, "UIMG", 4)) {
1199                 cmd_uimg(&cmdbuf[5]);
1200         }
1201
1202         else if (!strncasecmp(cmdbuf, "TIME", 4)) {
1203                 cmd_time();
1204         }
1205
1206         else if (!strncasecmp(cmdbuf, "AGUP", 4)) {
1207                 cmd_agup(&cmdbuf[5]);
1208         }
1209
1210         else if (!strncasecmp(cmdbuf, "ASUP", 4)) {
1211                 cmd_asup(&cmdbuf[5]);
1212         }
1213
1214         else if (!strncasecmp(cmdbuf, "GPEX", 4)) {
1215                 cmd_gpex(&cmdbuf[5]);
1216         }
1217
1218         else if (!strncasecmp(cmdbuf, "SPEX", 4)) {
1219                 cmd_spex(&cmdbuf[5]);
1220         }
1221
1222         else if (!strncasecmp(cmdbuf, "CONF", 4)) {
1223                 cmd_conf(&cmdbuf[5]);
1224         }
1225
1226         else if (!strncasecmp(cmdbuf, "SEEN", 4)) {
1227                 cmd_seen(&cmdbuf[5]);
1228         }
1229
1230         else if (!strncasecmp(cmdbuf, "VIEW", 4)) {
1231                 cmd_view(&cmdbuf[5]);
1232         }
1233
1234 #ifdef DEBUG_MEMORY_LEAKS
1235         else if (!strncasecmp(cmdbuf, "LEAK", 4)) {
1236                 dump_tracked();
1237         }
1238 #endif
1239
1240         else if (!DLoader_Exec_Cmd(cmdbuf)) {
1241                 cprintf("%d Unrecognized or unsupported command.\n", ERROR);
1242                }
1243
1244         /* Run any after-each-command outines registered by modules */
1245         PerformSessionHooks(EVT_CMD);
1246 }