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("1\n"); /* 1 = yes, this system supports the QNOP command */
 334         cprintf("000\n");
 335 }
 336
 337
 338 /*
 339  * returns an asterisk if there are any express messages waiting,
 340  * space otherwise.
 341  */
 342 char CtdlCheckExpress(void) {
 343         if (CC->FirstExpressMessage == NULL) {
 344                 return(' ');
 345         }
 346         else {
 347                 return('*');
 348         }
 349 }
 350
 351 void cmd_time(void)
 352 {
 353    time_t tv;
 354    struct tm *tmp;
 355
 356    tv = time(NULL);
 357    tmp = localtime(&tv);
 358
 359    /* timezone and daylight global variables are not portable. */
 360 #ifdef HAVE_STRUCT_TM_TM_GMTOFF
 361    cprintf("%d %ld|%ld|%d\n", CIT_OK, (long)tv, tmp->tm_gmtoff, tmp->tm_isdst);
 362 #else
 363    cprintf("%d %ld|%ld|%d\n", CIT_OK, (long)tv, timezone, tmp->tm_isdst);
 364 #endif
 365 }
 366
 367 /*
 368  * Check whether two hostnames match.
 369  * "Realname" should be an actual name of a client that is trying to connect;
 370  * "testname" should be the value we are comparing it with. The idea is that we
 371  * want to compare with both the abbreviated and fully-qualified versions of
 372  * "testname;" some people define "localhost" as "localhost.foo.com," etc.
 373  */
 374 static int hostnames_match(const char *realname, const char *testname) {
 375         struct hostent *he;
 376         int retval = 0;
 377
 378         if (!strcasecmp(realname, testname)) {
 379                 return(1);
 380         }
 381
 382 #ifdef HAVE_NONREENTRANT_NETDB
 383         begin_critical_section(S_NETDB);
 384 #endif
 385
 386         if ((he = gethostbyname(testname)) != NULL) {
 387                 if (!strcasecmp(realname, he->h_name)) {
 388                         retval = 1;
 389                 }
 390         }
 391
 392 #ifdef HAVE_NONREENTRANT_NETDB
 393         end_critical_section(S_NETDB);
 394 #endif
 395
 396         return retval;
 397 }
 398
 399 /*
 400  * check a hostname against the public_clients file
 401  */
 402 int is_public_client(char *where)
 403 {
 404         char buf[SIZ];
 405         FILE *fp;
 406
 407         lprintf(9, "Checking whether %s is a public client\n", where);
 408
 409         if (hostnames_match(where, "localhost")) return(1);
 410         if (hostnames_match(where, config.c_fqdn)) return(1);
 411
 412         fp = fopen("public_clients","r");
 413         if (fp == NULL) return(0);
 414
 415         while (fgets(buf, sizeof buf, fp)!=NULL) {
 416                 while (isspace((buf[strlen(buf)-1])))
 417                         buf[strlen(buf)-1] = 0;
 418                 if (hostnames_match(where,buf)) {
 419                         fclose(fp);
 420                         return(1);
 421                 }
 422         }
 423
 424         fclose(fp);
 425         return(0);
 426 }
 427
 428
 429 /*
 430  * the client is identifying itself to the server
 431  */
 432 void cmd_iden(char *argbuf)
 433 {
 434         int dev_code;
 435         int cli_code;
 436         int rev_level;
 437         char desc[SIZ];
 438         char from_host[SIZ];
 439         struct in_addr addr;
 440         int do_lookup = 0;
 441
 442         if (num_parms(argbuf)<4) {
 443                 cprintf("%d usage error\n",ERROR);
 444                 return;
 445         }
 446
 447         dev_code = extract_int(argbuf,0);
 448         cli_code = extract_int(argbuf,1);
 449         rev_level = extract_int(argbuf,2);
 450         extract(desc,argbuf,3);
 451
 452         safestrncpy(from_host, config.c_fqdn, sizeof from_host);
 453         from_host[sizeof from_host - 1] = 0;
 454         if (num_parms(argbuf)>=5) extract(from_host,argbuf,4);
 455
 456         CC->cs_clientdev = dev_code;
 457         CC->cs_clienttyp = cli_code;
 458         CC->cs_clientver = rev_level;
 459         safestrncpy(CC->cs_clientname, desc, sizeof CC->cs_clientname);
 460         CC->cs_clientname[31] = 0;
 461
 462         if (strlen(from_host) > 0) {
 463                 if (CC->is_local_socket) do_lookup = 1;
 464                 else if (is_public_client(CC->cs_host)) do_lookup = 1;
 465         }
 466
 467         if (do_lookup) {
 468                 lprintf(9, "Looking up hostname '%s'\n", from_host);
 469                 if ((addr.s_addr = inet_addr(from_host)) != -1) {
 470                         locate_host(CC->cs_host, sizeof CC->cs_host, &addr);
 471                 }
 472                 else {
 473                         safestrncpy(CC->cs_host, from_host, sizeof CC->cs_host);
 474                         CC->cs_host[sizeof CC->cs_host - 1] = 0;
 475                 }
 476         }
 477
 478         lprintf(7, "client %d/%d/%01d.%02d (%s)\n",
 479                 dev_code,
 480                 cli_code,
 481                 (rev_level / 100),
 482                 (rev_level % 100),
 483                 desc);
 484
 485         syslog(LOG_NOTICE,"session %d: client %d/%d/%01d.%02d (%s) from %s\n",
 486                 CC->cs_pid,
 487                 dev_code,
 488                 cli_code,
 489                 (rev_level / 100),
 490                 (rev_level % 100),
 491                 desc,
 492                 CC->cs_host);
 493         cprintf("%d Ok\n",CIT_OK);
 494 }
 495
 496
 497 /*
 498  * display system messages or help
 499  */
 500 void cmd_mesg(char *mname)
 501 {
 502         FILE *mfp;
 503         char targ[SIZ];
 504         char buf[SIZ];
 505         char *dirs[2];
 506
 507         extract(buf,mname,0);
 508
 509
 510         dirs[0]=mallok(64);
 511         dirs[1]=mallok(64);
 512         strcpy(dirs[0],"messages");
 513         strcpy(dirs[1],"help");
 514         mesg_locate(targ,sizeof targ,buf,2,(const char **)dirs);
 515         phree(dirs[0]);
 516         phree(dirs[1]);
 517
 518
 519         if (strlen(targ)==0) {
 520                 cprintf("%d '%s' not found.\n",ERROR,mname);
 521                 return;
 522         }
 523
 524         mfp = fopen(targ,"r");
 525         if (mfp==NULL) {
 526                 cprintf("%d Cannot open '%s': %s\n",
 527                         ERROR,targ,strerror(errno));
 528                 return;
 529         }
 530         cprintf("%d %s\n",LISTING_FOLLOWS,buf);
 531
 532         while (fgets(buf, (SIZ-1), mfp)!=NULL) {
 533                 buf[strlen(buf)-1] = 0;
 534                 do_help_subst(buf);
 535                 cprintf("%s\n",buf);
 536         }
 537
 538         fclose(mfp);
 539         cprintf("000\n");
 540 }
 541
 542
 543 /*
 544  * enter system messages or help
 545  */
 546 void cmd_emsg(char *mname)
 547 {
 548         FILE *mfp;
 549         char targ[SIZ];
 550         char buf[SIZ];
 551         char *dirs[2];
 552         int a;
 553
 554         if (CtdlAccessCheck(ac_aide)) return;
 555
 556         extract(buf,mname,0);
 557         for (a=0; a<strlen(buf); ++a) {         /* security measure */
 558                 if (buf[a] == '/') buf[a] = '.';
 559         }
 560
 561         dirs[0]=mallok(64);
 562         dirs[1]=mallok(64);
 563         strcpy(dirs[0],"messages");
 564         strcpy(dirs[1],"help");
 565         mesg_locate(targ,sizeof targ,buf,2,(const char**)dirs);
 566         phree(dirs[0]);
 567         phree(dirs[1]);
 568
 569         if (strlen(targ)==0) {
 570                 snprintf(targ, sizeof targ, "./help/%s", buf);
 571         }
 572
 573         mfp = fopen(targ,"w");
 574         if (mfp==NULL) {
 575                 cprintf("%d Cannot open '%s': %s\n",
 576                         ERROR,targ,strerror(errno));
 577                 return;
 578         }
 579         cprintf("%d %s\n", SEND_LISTING, targ);
 580
 581         while (client_gets(buf), strcmp(buf, "000")) {
 582                 fprintf(mfp, "%s\n", buf);
 583         }
 584
 585         fclose(mfp);
 586 }
 587
 588
 589 /* Don't show the names of private rooms unless the viewing
 590  * user also knows the rooms.
 591  */
 592 void GenerateRoomDisplay(char *real_room,
 593                         struct CitContext *viewed,
 594                         struct CitContext *viewer) {
 595
 596         strcpy(real_room, viewed->quickroom.QRname);
 597         if (viewed->quickroom.QRflags & QR_MAILBOX) {
 598                 strcpy(real_room, &real_room[11]);
 599         }
 600         if (viewed->quickroom.QRflags & QR_PRIVATE) {
 601                 if ( (CtdlRoomAccess(&viewed->quickroom, &viewer->usersupp)
 602                    & UA_KNOWN) == 0) {
 603                         strcpy(real_room, "<private room>");
 604                 }
 605         }
 606
 607         if (viewed->cs_flags & CS_CHAT) {
 608                 while (strlen(real_room) < 14)
 609                         strcat(real_room, " ");
 610
 611                 strcpy(&real_room[14], "<chat>");
 612         }
 613
 614 }
 615
 616 /*
 617  * Convenience function.
 618  */
 619 int CtdlAccessCheck(int required_level) {
 620
 621         if (CC->internal_pgm) return(0);
 622         if (required_level >= ac_internal) {
 623                 cprintf("%d This is not a user-level command.\n",
 624                         ERROR+HIGHER_ACCESS_REQUIRED);
 625                 return(-1);
 626         }
 627
 628         if (CC->usersupp.axlevel >= 6) return(0);
 629         if (required_level >= ac_aide) {
 630                 cprintf("%d This command requires Aide access.\n",
 631                         ERROR+HIGHER_ACCESS_REQUIRED);
 632                 return(-1);
 633         }
 634
 635         if (is_room_aide()) return(0);
 636         if (required_level >= ac_room_aide) {
 637                 cprintf("%d This command requires Aide or Room Aide access.\n",
 638                         ERROR + HIGHER_ACCESS_REQUIRED);
 639                 return(-1);
 640         }
 641
 642         if (CC->logged_in) return(0);
 643         if (required_level >= ac_logged_in) {
 644                 cprintf("%d Not logged in.\n", ERROR+NOT_LOGGED_IN);
 645                 return(-1);
 646         }
 647
 648         /* shhh ... succeed quietly */
 649         return(0);
 650 }
 651
 652
 653
 654 /*
 655  * Terminate another running session
 656  */
 657 void cmd_term(char *cmdbuf)
 658 {
 659         int session_num;
 660         struct CitContext *ccptr;
 661         int found_it = 0;
 662         int allowed = 0;
 663
 664         session_num = extract_int(cmdbuf, 0);
 665         if (session_num == CC->cs_pid) {
 666                 cprintf("%d You can't kill your own session.\n", ERROR);
 667                 return;
 668         }
 669
 670         lprintf(9, "Locating session to kill\n");
 671         begin_critical_section(S_SESSION_TABLE);
 672         for (ccptr = ContextList; ccptr != NULL; ccptr = ccptr->next) {
 673                 if (session_num == ccptr->cs_pid) {
 674                         found_it = 1;
 675                         if ((ccptr->usersupp.usernum == CC->usersupp.usernum)
 676                            || (CC->usersupp.axlevel >= 6)) {
 677                                 allowed = 1;
 678                                 ccptr->kill_me = 1;
 679                         }
 680                         else {
 681                                 allowed = 0;
 682                         }
 683                 }
 684         }
 685         end_critical_section(S_SESSION_TABLE);
 686
 687         if (found_it) {
 688                 if (allowed) {
 689                         cprintf("%d Session terminated.\n", CIT_OK);
 690                 }
 691                 else {
 692                         cprintf("%d You are not allowed to do that.\n",
 693                                 ERROR + HIGHER_ACCESS_REQUIRED);
 694                 }
 695         }
 696         else {
 697                 cprintf("%d No such session.\n", ERROR);
 698         }
 699 }
 700
 701
 702
 703
 704
 705 /*
 706  * get the paginator prompt
 707  */
 708 void cmd_more(void) {
 709         cprintf("%d %s\n", CIT_OK, config.c_moreprompt);
 710 }
 711
 712 /*
 713  * echo
 714  */
 715 void cmd_echo(char *etext)
 716 {
 717         cprintf("%d %s\n", CIT_OK, etext);
 718 }
 719
 720
 721
 722 /*
 723  * identify as internal program
 724  */
 725 void cmd_ipgm(char *argbuf)
 726 {
 727         int secret;
 728
 729         secret = extract_int(argbuf, 0);
 730         if (secret == config.c_ipgm_secret) {
 731                 CC->internal_pgm = 1;
 732                 strcpy(CC->curr_user, "<internal program>");
 733                 CC->cs_flags = CC->cs_flags|CS_STEALTH;
 734                 cprintf("%d Authenticated as an internal program.\n",CIT_OK);
 735         }
 736         else {
 737                 cprintf("%d Authentication failed.\n",ERROR);
 738                 lprintf(3, "Warning: ipgm authentication failed.\n");
 739         }
 740 }
 741
 742
 743 /*
 744  * Shut down the server
 745  */
 746 void cmd_down(void) {
 747
 748         if (CtdlAccessCheck(ac_aide)) return;
 749
 750         cprintf("%d Shutting down server.  Goodbye.\n", CIT_OK);
 751         time_to_die = 1;
 752 }
 753
 754 /*
 755  * Schedule or cancel a server shutdown
 756  */
 757 void cmd_scdn(char *argbuf)
 758 {
 759         int new_state;
 760
 761         if (CtdlAccessCheck(ac_aide)) return;
 762
 763         new_state = extract_int(argbuf, 0);
 764         if ((new_state == 0) || (new_state == 1)) {
 765                 ScheduledShutdown = new_state;
 766         }
 767         cprintf("%d %d\n", CIT_OK, ScheduledShutdown);
 768 }
 769
 770
 771 /*
 772  * Set or unset asynchronous protocol mode
 773  */
 774 void cmd_asyn(char *argbuf)
 775 {
 776         int new_state;
 777
 778         new_state = extract_int(argbuf, 0);
 779         if ((new_state == 0) || (new_state == 1)) {
 780                 CC->is_async = new_state;
 781         }
 782         cprintf("%d %d\n", CIT_OK, CC->is_async);
 783 }
 784
 785
 786 /*
 787  * Generate a "nonce" for APOP-style authentication.
 788  *
 789  * RFC 1725 et al specify a PID to be placed in front of the nonce.
 790  * Quoth BTX: That would be stupid.
 791  */
 792 void generate_nonce(struct CitContext *con) {
 793         struct timeval tv;
 794
 795         memset(con->cs_nonce, NONCE_SIZE, 0);
 796         gettimeofday(&tv, NULL);
 797         memset(con->cs_nonce, NONCE_SIZE, 0);
 798         snprintf(con->cs_nonce, NONCE_SIZE, "<%d%ld@%s>",
 799                 rand(), (long)tv.tv_usec, config.c_fqdn);
 800 }
 801
 802
 803
 804
 805 /*
 806  * Back-end function for starting a session
 807  */
 808 void begin_session(struct CitContext *con)
 809 {
 810         int len;
 811         struct sockaddr_in sin;
 812
 813         /*
 814          * Initialize some variables specific to our context.
 815          */
 816         con->logged_in = 0;
 817         con->internal_pgm = 0;
 818         con->download_fp = NULL;
 819         con->upload_fp = NULL;
 820         con->FirstExpressMessage = NULL;
 821         time(&con->lastcmd);
 822         time(&con->lastidle);
 823         strcpy(con->lastcmdname, "    ");
 824         strcpy(con->cs_clientname, "(unknown)");
 825         strcpy(con->curr_user, NLI);
 826         strcpy(con->net_node,"");
 827         strcpy(con->fake_username, "");
 828         strcpy(con->fake_postname, "");
 829         strcpy(con->fake_hostname, "");
 830         strcpy(con->fake_roomname, "");
 831         generate_nonce(con);
 832         snprintf(con->temp, sizeof con->temp, tmpnam(NULL));
 833         safestrncpy(con->cs_host, config.c_fqdn, sizeof con->cs_host);
 834         con->cs_host[sizeof con->cs_host - 1] = 0;
 835         len = sizeof sin;
 836         if (!CC->is_local_socket) {
 837                 if (!getpeername(con->client_socket,
 838                    (struct sockaddr *) &sin, &len))
 839                         locate_host(con->cs_host, sizeof con->cs_host, &sin.sin_addr);
 840         }
 841         else {
 842                 strcpy(con->cs_host, "");
 843         }
 844         con->cs_flags = 0;
 845         con->upload_type = UPL_FILE;
 846         con->dl_is_net = 0;
 847         con->FirstSessData = NULL;
 848
 849         con->nologin = 0;
 850         if ((config.c_maxsessions > 0)&&(num_sessions > config.c_maxsessions))
 851                 con->nologin = 1;
 852
 853         lprintf(3, "Session started.\n");
 854
 855         /* Run any session startup routines registered by loadable modules */
 856         PerformSessionHooks(EVT_START);
 857
 858         rec_log(CL_CONNECT, "");
 859 }
 860
 861
 862 void citproto_begin_session() {
 863         if (CC->nologin==1) {
 864                 cprintf("%d %s: Too many users are already online "
 865                         "(maximum is %d)\n",
 866                         ERROR+MAX_SESSIONS_EXCEEDED,
 867                         config.c_nodename, config.c_maxsessions);
 868         }
 869         else {
 870                 cprintf("%d %s Citadel/UX server ready.\n",
 871                         CIT_OK, config.c_nodename);
 872         }
 873 }
 874
 875
 876
 877
 878 /*
 879  * This loop recognizes all server commands.
 880  */
 881 void do_command_loop(void) {
 882         char cmdbuf[SIZ];
 883
 884         time(&CC->lastcmd);
 885         memset(cmdbuf, 0, sizeof cmdbuf); /* Clear it, just in case */
 886         if (client_gets(cmdbuf) < 1) {
 887                 lprintf(3, "Client socket is broken.  Ending session.\n");
 888                 CC->kill_me = 1;
 889                 return;
 890         }
 891         lprintf(5, "Citadel: %s\n", cmdbuf);
 892
 893         /*
 894          * Let other clients see the last command we executed, and
 895          * update the idle time, but not NOOP, QNOP, PEXP, or GEXP.
 896          */
 897         if ( (strncasecmp(cmdbuf, "NOOP", 4))
 898            && (strncasecmp(cmdbuf, "QNOP", 4))
 899            && (strncasecmp(cmdbuf, "PEXP", 4))
 900            && (strncasecmp(cmdbuf, "GEXP", 4)) ) {
 901                 strcpy(CC->lastcmdname, "    ");
 902                 safestrncpy(CC->lastcmdname, cmdbuf,
 903                         sizeof(CC->lastcmdname) );
 904                 time(&CC->lastidle);
 905         }
 906
 907         if ((strncasecmp(cmdbuf, "ENT0", 4))
 908            && (strncasecmp(cmdbuf, "MESG", 4))
 909            && (strncasecmp(cmdbuf, "MSGS", 4)))
 910         {
 911            CC->cs_flags &= ~CS_POSTING;
 912         }
 913
 914         if (!strncasecmp(cmdbuf,"NOOP",4)) {
 915                 cprintf("%d%cok\n",CIT_OK,CtdlCheckExpress());
 916         }
 917
 918         else if (!strncasecmp(cmdbuf,"QNOP",4)) {
 919                 /* do nothing, this command returns no response */
 920         }
 921
 922         else if (!strncasecmp(cmdbuf,"QUIT",4)) {
 923                 cprintf("%d Goodbye.\n",CIT_OK);
 924                 CC->kill_me = 1;
 925         }
 926
 927         else if (!strncasecmp(cmdbuf,"ASYN",4)) {
 928                 cmd_asyn(&cmdbuf[5]);
 929         }
 930
 931         else if (!strncasecmp(cmdbuf,"LOUT",4)) {
 932                 if (CC->logged_in) logout(CC);
 933                 cprintf("%d logged out.\n",CIT_OK);
 934         }
 935
 936         else if (!strncasecmp(cmdbuf,"USER",4)) {
 937                 cmd_user(&cmdbuf[5]);
 938         }
 939
 940         else if (!strncasecmp(cmdbuf,"PASS",4)) {
 941                 cmd_pass(&cmdbuf[5]);
 942         }
 943
 944         else if (!strncasecmp(cmdbuf,"NEWU",4)) {
 945                 cmd_newu(&cmdbuf[5]);
 946         }
 947
 948         else if (!strncasecmp(cmdbuf,"CREU",4)) {
 949                 cmd_creu(&cmdbuf[5]);
 950         }
 951
 952         else if (!strncasecmp(cmdbuf,"SETP",4)) {
 953                 cmd_setp(&cmdbuf[5]);
 954         }
 955
 956         else if (!strncasecmp(cmdbuf,"LRMS",4)) {
 957                 cmd_lrms(&cmdbuf[5]);
 958         }
 959
 960         else if (!strncasecmp(cmdbuf,"LKRA",4)) {
 961                 cmd_lkra(&cmdbuf[5]);
 962         }
 963
 964         else if (!strncasecmp(cmdbuf,"LKRN",4)) {
 965                 cmd_lkrn(&cmdbuf[5]);
 966         }
 967
 968         else if (!strncasecmp(cmdbuf,"LKRO",4)) {
 969                 cmd_lkro(&cmdbuf[5]);
 970         }
 971
 972         else if (!strncasecmp(cmdbuf,"LZRM",4)) {
 973                 cmd_lzrm(&cmdbuf[5]);
 974         }
 975
 976         else if (!strncasecmp(cmdbuf,"GETU",4)) {
 977                 cmd_getu();
 978         }
 979
 980         else if (!strncasecmp(cmdbuf,"SETU",4)) {
 981                 cmd_setu(&cmdbuf[5]);
 982         }
 983
 984         else if (!strncasecmp(cmdbuf,"GOTO",4)) {
 985                 cmd_goto(&cmdbuf[5]);
 986         }
 987
 988         else if (!strncasecmp(cmdbuf,"MSGS",4)) {
 989                 cmd_msgs(&cmdbuf[5]);
 990         }
 991
 992         else if (!strncasecmp(cmdbuf,"WHOK",4)) {
 993                 cmd_whok();
 994         }
 995
 996         else if (!strncasecmp(cmdbuf,"RDIR",4)) {
 997                 cmd_rdir();
 998         }
 999
1000         else if (!strncasecmp(cmdbuf,"MSG0",4)) {
1001                 cmd_msg0(&cmdbuf[5]);
1002         }
1003
1004         else if (!strncasecmp(cmdbuf,"MSG2",4)) {
1005                 cmd_msg2(&cmdbuf[5]);
1006         }
1007
1008         else if (!strncasecmp(cmdbuf,"MSG3",4)) {
1009                 cmd_msg3(&cmdbuf[5]);
1010         }
1011
1012         else if (!strncasecmp(cmdbuf,"MSG4",4)) {
1013                 cmd_msg4(&cmdbuf[5]);
1014         }
1015
1016         else if (!strncasecmp(cmdbuf,"OPNA",4)) {
1017                 cmd_opna(&cmdbuf[5]);
1018         }
1019
1020         else if (!strncasecmp(cmdbuf,"INFO",4)) {
1021                 cmd_info();
1022         }
1023
1024         else if (!strncasecmp(cmdbuf,"SLRP",4)) {
1025                 cmd_slrp(&cmdbuf[5]);
1026         }
1027
1028         else if (!strncasecmp(cmdbuf,"INVT",4)) {
1029                 cmd_invt_kick(&cmdbuf[5],1);
1030         }
1031
1032         else if (!strncasecmp(cmdbuf,"KICK",4)) {
1033                 cmd_invt_kick(&cmdbuf[5],0);
1034         }
1035
1036         else if (!strncasecmp(cmdbuf,"GETR",4)) {
1037                 cmd_getr();
1038         }
1039
1040         else if (!strncasecmp(cmdbuf,"SETR",4)) {
1041                 cmd_setr(&cmdbuf[5]);
1042         }
1043
1044         else if (!strncasecmp(cmdbuf,"GETA",4)) {
1045                 cmd_geta();
1046         }
1047
1048         else if (!strncasecmp(cmdbuf,"SETA",4)) {
1049                 cmd_seta(&cmdbuf[5]);
1050         }
1051
1052         else if (!strncasecmp(cmdbuf,"ENT0",4)) {
1053                 cmd_ent0(&cmdbuf[5]);
1054         }
1055
1056         else if (!strncasecmp(cmdbuf,"RINF",4)) {
1057                 cmd_rinf();
1058         }
1059
1060         else if (!strncasecmp(cmdbuf,"DELE",4)) {
1061                 cmd_dele(&cmdbuf[5]);
1062         }
1063
1064         else if (!strncasecmp(cmdbuf,"KILL",4)) {
1065                 cmd_kill(&cmdbuf[5]);
1066         }
1067
1068         else if (!strncasecmp(cmdbuf,"CRE8",4)) {
1069                 cmd_cre8(&cmdbuf[5]);
1070         }
1071
1072         else if (!strncasecmp(cmdbuf,"MOVE",4)) {
1073                 cmd_move(&cmdbuf[5]);
1074         }
1075
1076         else if (!strncasecmp(cmdbuf,"FORG",4)) {
1077                 cmd_forg();
1078         }
1079
1080         else if (!strncasecmp(cmdbuf,"MESG",4)) {
1081                 cmd_mesg(&cmdbuf[5]);
1082         }
1083
1084         else if (!strncasecmp(cmdbuf,"EMSG",4)) {
1085                 cmd_emsg(&cmdbuf[5]);
1086         }
1087
1088         else if (!strncasecmp(cmdbuf,"GNUR",4)) {
1089                 cmd_gnur();
1090         }
1091
1092         else if (!strncasecmp(cmdbuf,"VALI",4)) {
1093                 cmd_vali(&cmdbuf[5]);
1094         }
1095
1096         else if (!strncasecmp(cmdbuf,"EINF",4)) {
1097                 cmd_einf(&cmdbuf[5]);
1098         }
1099
1100         else if (!strncasecmp(cmdbuf,"LIST",4)) {
1101                 cmd_list();
1102         }
1103
1104         else if (!strncasecmp(cmdbuf,"CHEK",4)) {
1105                 cmd_chek();
1106         }
1107
1108         else if (!strncasecmp(cmdbuf,"DELF",4)) {
1109                 cmd_delf(&cmdbuf[5]);
1110         }
1111
1112         else if (!strncasecmp(cmdbuf,"MOVF",4)) {
1113                 cmd_movf(&cmdbuf[5]);
1114         }
1115
1116         else if (!strncasecmp(cmdbuf,"NETF",4)) {
1117                 cmd_netf(&cmdbuf[5]);
1118         }
1119
1120         else if (!strncasecmp(cmdbuf,"OPEN",4)) {
1121                 cmd_open(&cmdbuf[5]);
1122         }
1123
1124         else if (!strncasecmp(cmdbuf,"CLOS",4)) {
1125                 cmd_clos();
1126         }
1127
1128         else if (!strncasecmp(cmdbuf,"UOPN",4)) {
1129                 cmd_uopn(&cmdbuf[5]);
1130         }
1131
1132         else if (!strncasecmp(cmdbuf,"UCLS",4)) {
1133                 cmd_ucls(&cmdbuf[5]);
1134         }
1135
1136         else if (!strncasecmp(cmdbuf,"READ",4)) {
1137                 cmd_read(&cmdbuf[5]);
1138         }
1139
1140         else if (!strncasecmp(cmdbuf,"WRIT",4)) {
1141                 cmd_writ(&cmdbuf[5]);
1142         }
1143
1144         else if (!strncasecmp(cmdbuf,"QUSR",4)) {
1145                 cmd_qusr(&cmdbuf[5]);
1146         }
1147
1148         else if (!strncasecmp(cmdbuf,"ECHO",4)) {
1149                 cmd_echo(&cmdbuf[5]);
1150         }
1151
1152         else if (!strncasecmp(cmdbuf,"OIMG",4)) {
1153                 cmd_oimg(&cmdbuf[5]);
1154         }
1155
1156         else if (!strncasecmp(cmdbuf,"MORE",4)) {
1157                 cmd_more();
1158         }
1159
1160         else if (!strncasecmp(cmdbuf,"NDOP",4)) {
1161                 cmd_ndop(&cmdbuf[5]);
1162         }
1163
1164         else if (!strncasecmp(cmdbuf,"NUOP",4)) {
1165                 cmd_nuop(&cmdbuf[5]);
1166         }
1167
1168         else if (!strncasecmp(cmdbuf,"LFLR",4)) {
1169                 cmd_lflr();
1170         }
1171
1172         else if (!strncasecmp(cmdbuf,"CFLR",4)) {
1173                 cmd_cflr(&cmdbuf[5]);
1174         }
1175
1176         else if (!strncasecmp(cmdbuf,"KFLR",4)) {
1177                 cmd_kflr(&cmdbuf[5]);
1178         }
1179
1180         else if (!strncasecmp(cmdbuf,"EFLR",4)) {
1181                 cmd_eflr(&cmdbuf[5]);
1182         }
1183
1184         else if (!strncasecmp(cmdbuf,"IDEN",4)) {
1185                 cmd_iden(&cmdbuf[5]);
1186         }
1187
1188         else if (!strncasecmp(cmdbuf,"IPGM",4)) {
1189                 cmd_ipgm(&cmdbuf[5]);
1190         }
1191
1192         else if (!strncasecmp(cmdbuf,"TERM",4)) {
1193                 cmd_term(&cmdbuf[5]);
1194         }
1195
1196         else if (!strncasecmp(cmdbuf,"DOWN",4)) {
1197                 cmd_down();
1198         }
1199
1200         else if (!strncasecmp(cmdbuf,"SCDN",4)) {
1201                 cmd_scdn(&cmdbuf[5]);
1202         }
1203
1204         else if (!strncasecmp(cmdbuf, "UIMG", 4)) {
1205                 cmd_uimg(&cmdbuf[5]);
1206         }
1207
1208         else if (!strncasecmp(cmdbuf, "TIME", 4)) {
1209                 cmd_time();
1210         }
1211
1212         else if (!strncasecmp(cmdbuf, "AGUP", 4)) {
1213                 cmd_agup(&cmdbuf[5]);
1214         }
1215
1216         else if (!strncasecmp(cmdbuf, "ASUP", 4)) {
1217                 cmd_asup(&cmdbuf[5]);
1218         }
1219
1220         else if (!strncasecmp(cmdbuf, "GPEX", 4)) {
1221                 cmd_gpex(&cmdbuf[5]);
1222         }
1223
1224         else if (!strncasecmp(cmdbuf, "SPEX", 4)) {
1225                 cmd_spex(&cmdbuf[5]);
1226         }
1227
1228         else if (!strncasecmp(cmdbuf, "CONF", 4)) {
1229                 cmd_conf(&cmdbuf[5]);
1230         }
1231
1232         else if (!strncasecmp(cmdbuf, "SEEN", 4)) {
1233                 cmd_seen(&cmdbuf[5]);
1234         }
1235
1236         else if (!strncasecmp(cmdbuf, "GTSN", 4)) {
1237                 cmd_gtsn(&cmdbuf[5]);
1238         }
1239
1240         else if (!strncasecmp(cmdbuf, "VIEW", 4)) {
1241                 cmd_view(&cmdbuf[5]);
1242         }
1243
1244 #ifdef DEBUG_MEMORY_LEAKS
1245         else if (!strncasecmp(cmdbuf, "LEAK", 4)) {
1246                 dump_tracked();
1247         }
1248 #endif
1249
1250         else if (!DLoader_Exec_Cmd(cmdbuf)) {
1251                 cprintf("%d Unrecognized or unsupported command.\n", ERROR);
1252                }
1253
1254         /* Run any after-each-command outines registered by modules */
1255         PerformSessionHooks(EVT_CMD);
1256 }