citadel/citserver.c

   1 /*
   2  * $Id$
   3  *
   4  * Main source module for the Citadel server
   5  *
   6  */
   7
   8 #include "sysdep.h"
   9 #include <stdlib.h>
  10 #include <unistd.h>
  11 #include <stdio.h>
  12 #include <fcntl.h>
  13 #include <signal.h>
  14 #include <time.h>
  15 #include <ctype.h>
  16 #include <string.h>
  17 #include <errno.h>
  18 #include <limits.h>
  19 #include <syslog.h>
  20 /* #include <dlfcn.h> */
  21 #include <netdb.h>
  22 #include <sys/types.h>
  23 #include <sys/socket.h>
  24 #include <sys/time.h>
  25 #include <netinet/in.h>
  26 #include <arpa/inet.h>
  27 #include "citadel.h"
  28 #include "server.h"
  29 #include "sysdep_decls.h"
  30 #include "citserver.h"
  31 #include "config.h"
  32 #include "database.h"
  33 #include "housekeeping.h"
  34 #include "user_ops.h"
  35 #include "logging.h"
  36 #include "msgbase.h"
  37 #include "support.h"
  38 #include "locate_host.h"
  39 #include "room_ops.h"
  40 #include "file_ops.h"
  41 #include "dynloader.h"
  42 #include "policy.h"
  43 #include "control.h"
  44 #include "tools.h"
  45
  46 struct CitContext *ContextList = NULL;
  47 char *unique_session_numbers;
  48 int ScheduledShutdown = 0;
  49 int do_defrag = 0;
  50
  51 /*
  52  * Various things that need to be initialized at startup
  53  */
  54 void master_startup(void) {
  55         struct timeval tv;
  56
  57         lprintf(7, "Opening databases\n");
  58         open_databases();
  59
  60         if (do_defrag) {
  61                 defrag_databases();
  62         }
  63
  64         cdb_begin_transaction();
  65
  66         check_ref_counts();
  67
  68         lprintf(7, "Creating base rooms (if necessary)\n");
  69         create_room(BASEROOM,           0, "", 0);
  70         create_room(AIDEROOM,           3, "", 0);
  71         create_room(SYSCONFIGROOM,      3, "", 0);
  72         create_room(config.c_twitroom,  0, "", 0);
  73
  74         lprintf(7, "Seeding the pseudo-random number generator...\n");
  75         gettimeofday(&tv, NULL);
  76         srand(tv.tv_usec);
  77
  78         cdb_end_transaction();
  79 }
  80
  81 /*
  82  * Cleanup routine to be called when the server is shutting down.
  83  */
  84 void master_cleanup(void) {
  85         struct CleanupFunctionHook *fcn;
  86
  87         /* Cancel all running sessions */
  88         lprintf(7, "Cancelling running sessions...\n");
  89
  90 /* FIXME do something here
  91         while (ContextList != NULL) {
  92                 }
  93  */
  94
  95         /* Run any cleanup routines registered by loadable modules */
  96         for (fcn = CleanupHookTable; fcn != NULL; fcn = fcn->next) {
  97                 (*fcn->h_function_pointer)();
  98                 }
  99
 100         /* Close databases */
 101         lprintf(7, "Closing databases\n");
 102         close_databases();
 103
 104         /* Do system-dependent stuff */
 105         sysdep_master_cleanup();
 106
 107         /* Now go away. */
 108         lprintf(3, "citserver: exiting.\n");
 109         fflush(stdout); fflush(stderr);
 110         exit(0);
 111         }
 112
 113
 114 /*
 115  * Free any per-session data allocated by modules or whatever
 116  */
 117 void deallocate_user_data(struct CitContext *con)
 118 {
 119         struct CtdlSessData *ptr;
 120
 121         begin_critical_section(S_SESSION_TABLE);
 122         while (con->FirstSessData != NULL) {
 123                 lprintf(9, "Deallocating user data symbol %ld\n",
 124                         con->FirstSessData->sym_id);
 125                 if (con->FirstSessData->sym_data != NULL)
 126                         phree(con->FirstSessData->sym_data);
 127                 ptr = con->FirstSessData->next;
 128                 phree(con->FirstSessData);
 129                 con->FirstSessData = ptr;
 130         }
 131         end_critical_section(S_SESSION_TABLE);
 132 }
 133
 134
 135
 136
 137 /*
 138  * Terminate a session and remove its context data structure.
 139  */
 140 void RemoveContext (struct CitContext *con)
 141 {
 142         struct CitContext *ptr = NULL;
 143         struct CitContext *ToFree = NULL;
 144
 145         lprintf(9, "RemoveContext() called\n");
 146         if (con==NULL) {
 147                 lprintf(5, "WARNING: RemoveContext() called with NULL!\n");
 148                 return;
 149                 }
 150
 151         /* Remove the context from the global context list.  This needs
 152          * to get done FIRST to avoid concurrency problems.  It is *vitally*
 153          * important to keep num_sessions accurate!!
 154          */
 155         lprintf(7, "Removing context for session %d\n", con->cs_pid);
 156         begin_critical_section(S_SESSION_TABLE);
 157         if (ContextList == con) {
 158                 ToFree = ContextList;
 159                 ContextList = ContextList->next;
 160                 --num_sessions;
 161                 }
 162         else {
 163                 for (ptr = ContextList; ptr != NULL; ptr = ptr->next) {
 164                         if (ptr->next == con) {
 165                                 ToFree = ptr->next;
 166                                 ptr->next = ptr->next->next;
 167                                 --num_sessions;
 168                                 }
 169                         }
 170                 }
 171         end_critical_section(S_SESSION_TABLE);
 172
 173         if (ToFree == NULL) {
 174                 lprintf(9, "RemoveContext() found nothing to remove\n");
 175                 return;
 176         }
 177
 178         /* Run any cleanup routines registered by loadable modules.
 179          * Note 1: This must occur *before* deallocate_user_data() because the
 180          *         cleanup functions might touch dynamic session data.
 181          * Note 2: We have to "become_session()" because the cleanup functions
 182          *         might make references to "CC" assuming it's the right one.
 183          */
 184         become_session(con);
 185         PerformSessionHooks(EVT_STOP);
 186         become_session(NULL);
 187
 188         /* Now handle all of the administrivia. */
 189         lprintf(7, "Calling logout(%d)\n", con->cs_pid);
 190         logout(con);
 191
 192         rec_log(CL_TERMINATE, con->curr_user);
 193         unlink(con->temp);
 194         lprintf(3, "citserver[%3d]: ended.\n", con->cs_pid);
 195
 196
 197         syslog(LOG_NOTICE,"session %d: ended", con->cs_pid);
 198
 199         /* Deallocate any user-data attached to this session */
 200         deallocate_user_data(con);
 201
 202         /* If the client is still connected, blow 'em away. */
 203         lprintf(7, "Closing socket %d\n", con->client_socket);
 204         close(con->client_socket);
 205
 206         /* Tell the housekeeping thread to check to see if this is the time
 207          * to initiate a scheduled shutdown event.
 208          */
 209         enter_housekeeping_cmd("SCHED_SHUTDOWN");
 210
 211         /* Free up the memory used by this context */
 212         phree(con);
 213
 214         lprintf(7, "Done with RemoveContext()\n");
 215 }
 216
 217
 218
 219 /*
 220  * Get a dynamic symbol number for per-session user data.
 221  * This API call should be made only ONCE per symbol per citserver run.
 222  */
 223 int CtdlGetDynamicSymbol()
 224 {
 225         static unsigned int next_symbol = SYM_MAX;
 226         return ++next_symbol;
 227 }
 228
 229
 230
 231 /*
 232  * Return a pointer to some generic per-session user data.
 233  * (This function returns NULL if the requested symbol is not allocated.)
 234  *
 235  * NOTE: we use critical sections for allocating and de-allocating these,
 236  *       but not for locating one.
 237  */
 238 void *CtdlGetUserData(unsigned long requested_sym)
 239 {
 240         struct CtdlSessData *ptr;
 241
 242         for (ptr = CC->FirstSessData; ptr != NULL; ptr = ptr->next)
 243                 if (ptr->sym_id == requested_sym)
 244                         return(ptr->sym_data);
 245
 246         lprintf(2, "ERROR! CtdlGetUserData(%ld) symbol not allocated\n",
 247                 requested_sym);
 248         return NULL;
 249 }
 250
 251
 252 /*
 253  * Allocate some generic per-session user data.
 254  */
 255 void CtdlAllocUserData(unsigned long requested_sym, size_t num_bytes)
 256 {
 257         struct CtdlSessData *ptr;
 258
 259         lprintf(9, "CtdlAllocUserData(%ld) called\n", requested_sym);
 260
 261         /* Fail silently if the symbol is already registered. */
 262         for (ptr = CC->FirstSessData; ptr != NULL; ptr = ptr->next)  {
 263                 if (ptr->sym_id == requested_sym) {
 264                         return;
 265                 }
 266         }
 267
 268         /* Grab us some memory!  Dem's good eatin' !!  */
 269         ptr = mallok(sizeof(struct CtdlSessData));
 270         ptr->sym_id = requested_sym;
 271         ptr->sym_data = mallok(num_bytes);
 272         memset(ptr->sym_data, 0, num_bytes);
 273
 274         begin_critical_section(S_SESSION_TABLE);
 275         ptr->next = CC->FirstSessData;
 276         CC->FirstSessData = ptr;
 277         end_critical_section(S_SESSION_TABLE);
 278
 279         lprintf(9, "CtdlAllocUserData(%ld) finished\n", requested_sym);
 280 }
 281
 282
 283 /*
 284  * Change the size of a buffer allocated with CtdlAllocUserData()
 285  */
 286 void CtdlReallocUserData(unsigned long requested_sym, size_t num_bytes)
 287 {
 288         struct CtdlSessData *ptr;
 289
 290         for (ptr = CC->FirstSessData; ptr != NULL; ptr = ptr->next)  {
 291                 if (ptr->sym_id == requested_sym) {
 292                         ptr->sym_data = reallok(ptr->sym_data, num_bytes);
 293                         return;
 294                 }
 295         }
 296
 297         lprintf(2, "CtdlReallocUserData() ERROR: symbol %ld not found!\n",
 298                 requested_sym);
 299 }
 300
 301
 302
 303
 304
 305
 306 /*
 307  * cmd_info()  -  tell the client about this server
 308  */
 309 void cmd_info(void) {
 310         cprintf("%d Server info:\n", LISTING_FOLLOWS);
 311         cprintf("%d\n", CC->cs_pid);
 312         cprintf("%s\n", config.c_nodename);
 313         cprintf("%s\n", config.c_humannode);
 314         cprintf("%s\n", config.c_fqdn);
 315         cprintf("%s\n", CITADEL);
 316         cprintf("%d\n", REV_LEVEL);
 317         cprintf("%s\n", config.c_bbs_city);
 318         cprintf("%s\n", config.c_sysadm);
 319         cprintf("%d\n", SERVER_TYPE);
 320         cprintf("%s\n", config.c_moreprompt);
 321         cprintf("1\n"); /* 1 = yes, this system supports floors */
 322         cprintf("1\n"); /* 1 = we support the extended paging options */
 323         cprintf("%s\n", CC->cs_nonce);
 324         cprintf("000\n");
 325 }
 326
 327
 328 /*
 329  * returns an asterisk if there are any express messages waiting,
 330  * space otherwise.
 331  */
 332 char CtdlCheckExpress(void) {
 333         if (CC->FirstExpressMessage == NULL) {
 334                 return(' ');
 335                 }
 336         else {
 337                 return('*');
 338                 }
 339         }
 340
 341 void cmd_time(void)
 342 {
 343    time_t tv;
 344
 345    tv = time(NULL);
 346
 347    cprintf("%d %ld\n", OK, tv);
 348 }
 349
 350 /*
 351  * Check whether two hostnames match.
 352  * "Realname" should be an actual name of a client that is trying to connect;
 353  * "testname" should be the value we are comparing it with. The idea is that we
 354  * want to compare with both the abbreviated and fully-qualified versions of
 355  * "testname;" some people define "localhost" as "localhost.foo.com," etc.
 356  */
 357 static int hostnames_match(const char *realname, const char *testname) {
 358         struct hostent *he;
 359         int retval = 0;
 360
 361         if (!strcasecmp(realname, testname))
 362                 return 1;
 363
 364 #ifdef HAVE_NONREENTRANT_NETDB
 365         begin_critical_section(S_NETDB);
 366 #endif
 367
 368         if ((he = gethostbyname(testname)) != NULL)
 369                 if (!strcasecmp(realname, he->h_name))
 370                         retval = 1;
 371
 372 #ifdef HAVE_NONREENTRANT_NETDB
 373         end_critical_section(S_NETDB);
 374 #endif
 375
 376         return retval;
 377         }
 378
 379 /*
 380  * check a hostname against the public_clients file
 381  */
 382 int is_public_client(char *where)
 383 {
 384         char buf[256];
 385         FILE *fp;
 386
 387         lprintf(9, "Checking whether %s is a public client\n", where);
 388
 389         if (hostnames_match(where, "localhost")) return(1);
 390         if (hostnames_match(where, config.c_fqdn)) return(1);
 391
 392         fp = fopen("public_clients","r");
 393         if (fp == NULL) return(0);
 394
 395         while (fgets(buf,256,fp)!=NULL) {
 396                 while (isspace((buf[strlen(buf)-1])))
 397                         buf[strlen(buf)-1] = 0;
 398                 if (hostnames_match(where,buf)) {
 399                         fclose(fp);
 400                         return(1);
 401                         }
 402                 }
 403
 404         fclose(fp);
 405         return(0);
 406         }
 407
 408
 409 /*
 410  * the client is identifying itself to the server
 411  */
 412 void cmd_iden(char *argbuf)
 413 {
 414         int dev_code;
 415         int cli_code;
 416         int rev_level;
 417         char desc[256];
 418         char from_host[256];
 419         struct in_addr addr;
 420         int do_lookup = 0;
 421
 422         if (num_parms(argbuf)<4) {
 423                 cprintf("%d usage error\n",ERROR);
 424                 return;
 425         }
 426
 427         dev_code = extract_int(argbuf,0);
 428         cli_code = extract_int(argbuf,1);
 429         rev_level = extract_int(argbuf,2);
 430         extract(desc,argbuf,3);
 431
 432         safestrncpy(from_host, config.c_fqdn, sizeof from_host);
 433         from_host[sizeof from_host - 1] = 0;
 434         if (num_parms(argbuf)>=5) extract(from_host,argbuf,4);
 435
 436         CC->cs_clientdev = dev_code;
 437         CC->cs_clienttyp = cli_code;
 438         CC->cs_clientver = rev_level;
 439         safestrncpy(CC->cs_clientname, desc, sizeof CC->cs_clientname);
 440         CC->cs_clientname[31] = 0;
 441
 442         if (strlen(from_host) > 0) {
 443                 if (CC->is_local_socket) do_lookup = 1;
 444                 else if (is_public_client(CC->cs_host)) do_lookup = 1;
 445         }
 446
 447         if (do_lookup) {
 448                 lprintf(9, "Looking up hostname '%s'\n", from_host);
 449                 if ((addr.s_addr = inet_addr(from_host)) != -1) {
 450                         locate_host(CC->cs_host, &addr);
 451                 }
 452                 else {
 453                         safestrncpy(CC->cs_host, from_host, sizeof CC->cs_host);
 454                         CC->cs_host[24] = 0;
 455                 }
 456         }
 457
 458         lprintf(7, "client %d/%d/%01d.%02d (%s)\n",
 459                 dev_code,
 460                 cli_code,
 461                 (rev_level / 100),
 462                 (rev_level % 100),
 463                 desc);
 464
 465         syslog(LOG_NOTICE,"session %d: client %d/%d/%01d.%02d (%s) from %s\n",
 466                 CC->cs_pid,
 467                 dev_code,
 468                 cli_code,
 469                 (rev_level / 100),
 470                 (rev_level % 100),
 471                 desc,
 472                 CC->cs_host);
 473         cprintf("%d Ok\n",OK);
 474 }
 475
 476
 477 /*
 478  * display system messages or help
 479  */
 480 void cmd_mesg(char *mname)
 481 {
 482         FILE *mfp;
 483         char targ[256];
 484         char buf[256];
 485         char *dirs[2];
 486
 487         extract(buf,mname,0);
 488
 489
 490         dirs[0]=mallok(64);
 491         dirs[1]=mallok(64);
 492         strcpy(dirs[0],"messages");
 493         strcpy(dirs[1],"help");
 494         mesg_locate(targ,buf,2,dirs);
 495         phree(dirs[0]);
 496         phree(dirs[1]);
 497
 498
 499         if (strlen(targ)==0) {
 500                 cprintf("%d '%s' not found.\n",ERROR,mname);
 501                 return;
 502                 }
 503
 504         mfp = fopen(targ,"r");
 505         if (mfp==NULL) {
 506                 cprintf("%d Cannot open '%s': %s\n",
 507                         ERROR,targ,strerror(errno));
 508                 return;
 509                 }
 510         cprintf("%d %s\n",LISTING_FOLLOWS,buf);
 511
 512         while (fgets(buf,255,mfp)!=NULL) {
 513                 buf[strlen(buf)-1] = 0;
 514                 do_help_subst(buf);
 515                 cprintf("%s\n",buf);
 516                 }
 517
 518         fclose(mfp);
 519         cprintf("000\n");
 520         }
 521
 522
 523 /*
 524  * enter system messages or help
 525  */
 526 void cmd_emsg(char *mname)
 527 {
 528         FILE *mfp;
 529         char targ[256];
 530         char buf[256];
 531         char *dirs[2];
 532         int a;
 533
 534         if (CtdlAccessCheck(ac_aide)) return;
 535
 536         extract(buf,mname,0);
 537         for (a=0; a<strlen(buf); ++a) {         /* security measure */
 538                 if (buf[a] == '/') buf[a] = '.';
 539                 }
 540
 541         dirs[0]=mallok(64);
 542         dirs[1]=mallok(64);
 543         strcpy(dirs[0],"messages");
 544         strcpy(dirs[1],"help");
 545         mesg_locate(targ,buf,2,dirs);
 546         phree(dirs[0]);
 547         phree(dirs[1]);
 548
 549         if (strlen(targ)==0) {
 550                 snprintf(targ, sizeof targ, "./help/%s", buf);
 551                 }
 552
 553         mfp = fopen(targ,"w");
 554         if (mfp==NULL) {
 555                 cprintf("%d Cannot open '%s': %s\n",
 556                         ERROR,targ,strerror(errno));
 557                 return;
 558                 }
 559         cprintf("%d %s\n", SEND_LISTING, targ);
 560
 561         while (client_gets(buf), strcmp(buf, "000")) {
 562                 fprintf(mfp, "%s\n", buf);
 563                 }
 564
 565         fclose(mfp);
 566         }
 567
 568
 569 /* Don't show the names of private rooms unless the viewing
 570  * user also knows the rooms.
 571  */
 572 void GenerateRoomDisplay(char *real_room,
 573                         struct CitContext *viewed,
 574                         struct CitContext *viewer) {
 575
 576         strcpy(real_room, viewed->quickroom.QRname);
 577         if (viewed->quickroom.QRflags & QR_MAILBOX) {
 578                 strcpy(real_room, &real_room[11]);
 579         }
 580         if (viewed->quickroom.QRflags & QR_PRIVATE) {
 581                 if ( (CtdlRoomAccess(&viewed->quickroom, &viewer->usersupp)
 582                    & UA_KNOWN) == 0) {
 583                         strcpy(real_room, "<private room>");
 584                 }
 585         }
 586
 587         if (viewed->cs_flags & CS_CHAT) {
 588                 while (strlen(real_room) < 14)
 589                         strcat(real_room, " ");
 590
 591                 strcpy(&real_room[14], "<chat>");
 592         }
 593
 594 }
 595
 596 /*
 597  * Convenience function.
 598  */
 599 int CtdlAccessCheck(int required_level) {
 600
 601         if (CC->internal_pgm) return(0);
 602         if (required_level >= ac_internal) {
 603                 cprintf("%d This is not a user-level command.\n",
 604                         ERROR+HIGHER_ACCESS_REQUIRED);
 605                 return(-1);
 606         }
 607
 608         if (CC->usersupp.axlevel >= 6) return(0);
 609         if (required_level >= ac_aide) {
 610                 cprintf("%d This command requires Aide access.\n",
 611                         ERROR+HIGHER_ACCESS_REQUIRED);
 612                 return(-1);
 613         }
 614
 615         if (is_room_aide()) return(0);
 616         if (required_level >= ac_room_aide) {
 617                 cprintf("%d This command requires Aide or Room Aide access.\n",
 618                         ERROR + HIGHER_ACCESS_REQUIRED);
 619                 return(-1);
 620         }
 621
 622         if (CC->logged_in) return(0);
 623         if (required_level >= ac_logged_in) {
 624                 cprintf("%d Not logged in.\n", ERROR+NOT_LOGGED_IN);
 625                 return(-1);
 626         }
 627
 628         /* shhh ... succeed quietly */
 629         return(0);
 630 }
 631
 632
 633
 634 /*
 635  * Terminate another running session
 636  */
 637 void cmd_term(char *cmdbuf)
 638 {
 639         int session_num;
 640         struct CitContext *ccptr;
 641         int found_it = 0;
 642
 643         if (CtdlAccessCheck(ac_aide)) return;
 644
 645         session_num = extract_int(cmdbuf, 0);
 646         if (session_num == CC->cs_pid) {
 647                 cprintf("%d You can't kill your own session.\n", ERROR);
 648                 return;
 649                 }
 650
 651         lprintf(9, "Locating session to kill\n");
 652         begin_critical_section(S_SESSION_TABLE);
 653         for (ccptr = ContextList; ccptr != NULL; ccptr = ccptr->next) {
 654                 if (session_num == ccptr->cs_pid) {
 655                         ccptr->kill_me = 1;
 656                         found_it = 1;
 657                         }
 658                 }
 659         end_critical_section(S_SESSION_TABLE);
 660
 661         if (found_it) {
 662                 cprintf("%d Session terminated.\n", OK);
 663                 }
 664         else {
 665                 cprintf("%d No such session.\n", ERROR);
 666                 }
 667         }
 668
 669
 670
 671
 672
 673 /*
 674  * get the paginator prompt
 675  */
 676 void cmd_more(void) {
 677         cprintf("%d %s\n",OK,config.c_moreprompt);
 678         }
 679
 680 /*
 681  * echo
 682  */
 683 void cmd_echo(char *etext)
 684 {
 685         cprintf("%d %s\n",OK,etext);
 686         }
 687
 688
 689
 690 /*
 691  * identify as internal program
 692  */
 693 void cmd_ipgm(char *argbuf)
 694 {
 695         int secret;
 696
 697         secret = extract_int(argbuf, 0);
 698         if (secret == config.c_ipgm_secret) {
 699                 CC->internal_pgm = 1;
 700                 strcpy(CC->curr_user, "<internal program>");
 701                 CC->cs_flags = CC->cs_flags|CS_STEALTH;
 702                 cprintf("%d Authenticated as an internal program.\n",OK);
 703                 }
 704         else {
 705                 cprintf("%d Authentication failed.\n",ERROR);
 706                 lprintf(3, "Warning: ipgm authentication failed.\n");
 707                 }
 708         }
 709
 710
 711 /*
 712  * Shut down the server
 713  */
 714 void cmd_down(void) {
 715
 716         if (CtdlAccessCheck(ac_aide)) return;
 717
 718         cprintf("%d Shutting down server.  Goodbye.\n", OK);
 719         master_cleanup();
 720         }
 721
 722 /*
 723  * Schedule or cancel a server shutdown
 724  */
 725 void cmd_scdn(char *argbuf)
 726 {
 727         int new_state;
 728
 729         if (CtdlAccessCheck(ac_aide)) return;
 730
 731         new_state = extract_int(argbuf, 0);
 732         if ((new_state == 0) || (new_state == 1)) {
 733                 ScheduledShutdown = new_state;
 734                 }
 735         cprintf("%d %d\n", OK, ScheduledShutdown);
 736         }
 737
 738
 739 /*
 740  * Generate a "nonce" for APOP-style authentication.
 741  *
 742  * RFC 1725 et al specify a PID to be placed in front of the nonce.
 743  * Quoth BTX: That would be stupid.
 744  */
 745 void generate_nonce(struct CitContext *con) {
 746         struct timeval tv;
 747
 748         memset(con->cs_nonce, NONCE_SIZE, 0);
 749         gettimeofday(&tv, NULL);
 750         memset(con->cs_nonce, NONCE_SIZE, 0);
 751         snprintf(con->cs_nonce, NONCE_SIZE, "<%d%ld@%s>",
 752                 rand(), tv.tv_usec, config.c_fqdn);
 753 }
 754
 755
 756
 757
 758 /*
 759  * Back-end function for starting a session
 760  */
 761 void begin_session(struct CitContext *con)
 762 {
 763         int len;
 764         struct sockaddr_in sin;
 765
 766         /*
 767          * Initialize some variables specific to our context.
 768          */
 769         con->logged_in = 0;
 770         con->internal_pgm = 0;
 771         con->download_fp = NULL;
 772         con->upload_fp = NULL;
 773         con->FirstExpressMessage = NULL;
 774         time(&con->lastcmd);
 775         time(&con->lastidle);
 776         strcpy(con->lastcmdname, "    ");
 777         strcpy(con->cs_clientname, "(unknown)");
 778         strcpy(con->curr_user, NLI);
 779         strcpy(con->net_node,"");
 780         strcpy(con->fake_username, "");
 781         strcpy(con->fake_postname, "");
 782         strcpy(con->fake_hostname, "");
 783         strcpy(con->fake_roomname, "");
 784         generate_nonce(con);
 785         snprintf(con->temp, sizeof con->temp, tmpnam(NULL));
 786         safestrncpy(con->cs_host, config.c_fqdn, sizeof con->cs_host);
 787         con->cs_host[sizeof con->cs_host - 1] = 0;
 788         len = sizeof sin;
 789         if (!CC->is_local_socket) {
 790                 if (!getpeername(con->client_socket,
 791                    (struct sockaddr *) &sin, &len))
 792                         locate_host(con->cs_host, &sin.sin_addr);
 793         }
 794         else {
 795                 strcpy(con->cs_host, "");
 796         }
 797         con->cs_flags = 0;
 798         con->upload_type = UPL_FILE;
 799         con->dl_is_net = 0;
 800         con->FirstSessData = NULL;
 801
 802         con->nologin = 0;
 803         if ((config.c_maxsessions > 0)&&(num_sessions > config.c_maxsessions))
 804                 con->nologin = 1;
 805
 806         lprintf(3, "citserver[%3d]: started.\n", con->cs_pid);
 807
 808         /* Run any session startup routines registered by loadable modules */
 809         PerformSessionHooks(EVT_START);
 810
 811         rec_log(CL_CONNECT, "");
 812 }
 813
 814
 815 void citproto_begin_session() {
 816         if (CC->nologin==1) {
 817                 cprintf("%d %s: Too many users are already online "
 818                         "(maximum is %d)\n",
 819                         ERROR+MAX_SESSIONS_EXCEEDED,
 820                         config.c_nodename, config.c_maxsessions);
 821                 }
 822         else {
 823                 cprintf("%d %s Citadel/UX server ready.\n",
 824                         OK, config.c_nodename);
 825                 }
 826 }
 827
 828
 829
 830
 831 /*
 832  * This loop recognizes all server commands.
 833  */
 834 void do_command_loop(void) {
 835         char cmdbuf[256];
 836
 837         time(&CC->lastcmd);
 838         memset(cmdbuf, 0, sizeof cmdbuf); /* Clear it, just in case */
 839         if (client_gets(cmdbuf) < 1) {
 840                 lprintf(3, "Client socket is broken.  Ending session.\n");
 841                 CC->kill_me = 1;
 842                 return;
 843         }
 844         lprintf(5, "citserver[%3d]: %s\n", CC->cs_pid, cmdbuf);
 845
 846         /*
 847          * Let other clients see the last command we executed, and
 848          * update the idle time, but not NOOP, PEXP, or GEXP.
 849          */
 850         if ( (strncasecmp(cmdbuf, "NOOP", 4))
 851            && (strncasecmp(cmdbuf, "PEXP", 4))
 852            && (strncasecmp(cmdbuf, "GEXP", 4)) ) {
 853                 strcpy(CC->lastcmdname, "    ");
 854                 safestrncpy(CC->lastcmdname, cmdbuf,
 855                         sizeof(CC->lastcmdname) );
 856                 time(&CC->lastidle);
 857                 }
 858
 859         if ((strncasecmp(cmdbuf, "ENT0", 4))
 860            && (strncasecmp(cmdbuf, "MESG", 4))
 861            && (strncasecmp(cmdbuf, "MSGS", 4)))
 862         {
 863            CC->cs_flags &= ~CS_POSTING;
 864         }
 865
 866         if (!strncasecmp(cmdbuf,"NOOP",4)) {
 867                 cprintf("%d%cok\n",OK,CtdlCheckExpress());
 868                 }
 869
 870         else if (!strncasecmp(cmdbuf,"QUIT",4)) {
 871                 cprintf("%d Goodbye.\n",OK);
 872                 CC->kill_me = 1;
 873                 }
 874
 875         else if (!strncasecmp(cmdbuf,"LOUT",4)) {
 876                 if (CC->logged_in) logout(CC);
 877                 cprintf("%d logged out.\n",OK);
 878                 }
 879
 880         else if (!strncasecmp(cmdbuf,"USER",4)) {
 881                 cmd_user(&cmdbuf[5]);
 882                 }
 883
 884         else if (!strncasecmp(cmdbuf,"PASS",4)) {
 885                 cmd_pass(&cmdbuf[5]);
 886                 }
 887
 888         else if (!strncasecmp(cmdbuf,"NEWU",4)) {
 889                 cmd_newu(&cmdbuf[5]);
 890                 }
 891
 892         else if (!strncasecmp(cmdbuf,"SETP",4)) {
 893                 cmd_setp(&cmdbuf[5]);
 894                 }
 895
 896         else if (!strncasecmp(cmdbuf,"LRMS",4)) {
 897                 cmd_lrms(&cmdbuf[5]);
 898                 }
 899
 900         else if (!strncasecmp(cmdbuf,"LKRA",4)) {
 901                 cmd_lkra(&cmdbuf[5]);
 902                 }
 903
 904         else if (!strncasecmp(cmdbuf,"LKRN",4)) {
 905                 cmd_lkrn(&cmdbuf[5]);
 906                 }
 907
 908         else if (!strncasecmp(cmdbuf,"LKRO",4)) {
 909                 cmd_lkro(&cmdbuf[5]);
 910                 }
 911
 912         else if (!strncasecmp(cmdbuf,"LZRM",4)) {
 913                 cmd_lzrm(&cmdbuf[5]);
 914                 }
 915
 916         else if (!strncasecmp(cmdbuf,"GETU",4)) {
 917                 cmd_getu();
 918                 }
 919
 920         else if (!strncasecmp(cmdbuf,"SETU",4)) {
 921                 cmd_setu(&cmdbuf[5]);
 922                 }
 923
 924         else if (!strncasecmp(cmdbuf,"GOTO",4)) {
 925                 cmd_goto(&cmdbuf[5]);
 926                 }
 927
 928         else if (!strncasecmp(cmdbuf,"MSGS",4)) {
 929                 cmd_msgs(&cmdbuf[5]);
 930                 }
 931
 932         else if (!strncasecmp(cmdbuf,"WHOK",4)) {
 933                 cmd_whok();
 934                 }
 935
 936         else if (!strncasecmp(cmdbuf,"RDIR",4)) {
 937                 cmd_rdir();
 938                 }
 939
 940         else if (!strncasecmp(cmdbuf,"MSG0",4)) {
 941                 cmd_msg0(&cmdbuf[5]);
 942                 }
 943
 944         else if (!strncasecmp(cmdbuf,"MSG2",4)) {
 945                 cmd_msg2(&cmdbuf[5]);
 946                 }
 947
 948         else if (!strncasecmp(cmdbuf,"MSG3",4)) {
 949                 cmd_msg3(&cmdbuf[5]);
 950                 }
 951
 952         else if (!strncasecmp(cmdbuf,"MSG4",4)) {
 953                 cmd_msg4(&cmdbuf[5]);
 954                 }
 955
 956         else if (!strncasecmp(cmdbuf,"OPNA",4)) {
 957                 cmd_opna(&cmdbuf[5]);
 958                 }
 959
 960         else if (!strncasecmp(cmdbuf,"INFO",4)) {
 961                 cmd_info();
 962                 }
 963
 964         else if (!strncasecmp(cmdbuf,"SLRP",4)) {
 965                 cmd_slrp(&cmdbuf[5]);
 966                 }
 967
 968         else if (!strncasecmp(cmdbuf,"INVT",4)) {
 969                 cmd_invt_kick(&cmdbuf[5],1);
 970                 }
 971
 972         else if (!strncasecmp(cmdbuf,"KICK",4)) {
 973                 cmd_invt_kick(&cmdbuf[5],0);
 974                 }
 975
 976         else if (!strncasecmp(cmdbuf,"GETR",4)) {
 977                 cmd_getr();
 978                 }
 979
 980         else if (!strncasecmp(cmdbuf,"SETR",4)) {
 981                 cmd_setr(&cmdbuf[5]);
 982                 }
 983
 984         else if (!strncasecmp(cmdbuf,"GETA",4)) {
 985                 cmd_geta();
 986                 }
 987
 988         else if (!strncasecmp(cmdbuf,"SETA",4)) {
 989                 cmd_seta(&cmdbuf[5]);
 990                 }
 991
 992         else if (!strncasecmp(cmdbuf,"ENT0",4)) {
 993                 cmd_ent0(&cmdbuf[5]);
 994                 }
 995
 996         else if (!strncasecmp(cmdbuf,"ENT3",4)) {
 997                 cmd_ent3(&cmdbuf[5]);
 998                 }
 999
1000         else if (!strncasecmp(cmdbuf,"RINF",4)) {
1001                 cmd_rinf();
1002                 }
1003
1004         else if (!strncasecmp(cmdbuf,"DELE",4)) {
1005                 cmd_dele(&cmdbuf[5]);
1006                 }
1007
1008         else if (!strncasecmp(cmdbuf,"KILL",4)) {
1009                 cmd_kill(&cmdbuf[5]);
1010                 }
1011
1012         else if (!strncasecmp(cmdbuf,"CRE8",4)) {
1013                 cmd_cre8(&cmdbuf[5]);
1014                 }
1015
1016         else if (!strncasecmp(cmdbuf,"MOVE",4)) {
1017                 cmd_move(&cmdbuf[5]);
1018                 }
1019
1020         else if (!strncasecmp(cmdbuf,"FORG",4)) {
1021                 cmd_forg();
1022                 }
1023
1024         else if (!strncasecmp(cmdbuf,"MESG",4)) {
1025                 cmd_mesg(&cmdbuf[5]);
1026                 }
1027
1028         else if (!strncasecmp(cmdbuf,"EMSG",4)) {
1029                 cmd_emsg(&cmdbuf[5]);
1030                 }
1031
1032         else if (!strncasecmp(cmdbuf,"GNUR",4)) {
1033                 cmd_gnur();
1034                 }
1035
1036         else if (!strncasecmp(cmdbuf,"VALI",4)) {
1037                 cmd_vali(&cmdbuf[5]);
1038                 }
1039
1040         else if (!strncasecmp(cmdbuf,"EINF",4)) {
1041                 cmd_einf(&cmdbuf[5]);
1042                 }
1043
1044         else if (!strncasecmp(cmdbuf,"LIST",4)) {
1045                 cmd_list();
1046                 }
1047
1048         else if (!strncasecmp(cmdbuf,"CHEK",4)) {
1049                 cmd_chek();
1050                 }
1051
1052         else if (!strncasecmp(cmdbuf,"DELF",4)) {
1053                 cmd_delf(&cmdbuf[5]);
1054                 }
1055
1056         else if (!strncasecmp(cmdbuf,"MOVF",4)) {
1057                 cmd_movf(&cmdbuf[5]);
1058                 }
1059
1060         else if (!strncasecmp(cmdbuf,"NETF",4)) {
1061                 cmd_netf(&cmdbuf[5]);
1062                 }
1063
1064         else if (!strncasecmp(cmdbuf,"OPEN",4)) {
1065                 cmd_open(&cmdbuf[5]);
1066                 }
1067
1068         else if (!strncasecmp(cmdbuf,"CLOS",4)) {
1069                 cmd_clos();
1070                 }
1071
1072         else if (!strncasecmp(cmdbuf,"UOPN",4)) {
1073                 cmd_uopn(&cmdbuf[5]);
1074                 }
1075
1076         else if (!strncasecmp(cmdbuf,"UCLS",4)) {
1077                 cmd_ucls(&cmdbuf[5]);
1078                 }
1079
1080         else if (!strncasecmp(cmdbuf,"READ",4)) {
1081                 cmd_read(&cmdbuf[5]);
1082                 }
1083
1084         else if (!strncasecmp(cmdbuf,"WRIT",4)) {
1085                 cmd_writ(&cmdbuf[5]);
1086                 }
1087
1088         else if (!strncasecmp(cmdbuf,"QUSR",4)) {
1089                 cmd_qusr(&cmdbuf[5]);
1090                 }
1091
1092         else if (!strncasecmp(cmdbuf,"ECHO",4)) {
1093                 cmd_echo(&cmdbuf[5]);
1094                 }
1095
1096         else if (!strncasecmp(cmdbuf,"OIMG",4)) {
1097                 cmd_oimg(&cmdbuf[5]);
1098                 }
1099
1100         else if (!strncasecmp(cmdbuf,"MORE",4)) {
1101                 cmd_more();
1102                 }
1103
1104         else if (!strncasecmp(cmdbuf,"NETP",4)) {
1105                 cmd_netp(&cmdbuf[5]);
1106                 }
1107
1108         else if (!strncasecmp(cmdbuf,"NDOP",4)) {
1109                 cmd_ndop(&cmdbuf[5]);
1110                 }
1111
1112         else if (!strncasecmp(cmdbuf,"NUOP",4)) {
1113                 cmd_nuop(&cmdbuf[5]);
1114                 }
1115
1116         else if (!strncasecmp(cmdbuf,"LFLR",4)) {
1117                 cmd_lflr();
1118                 }
1119
1120         else if (!strncasecmp(cmdbuf,"CFLR",4)) {
1121                 cmd_cflr(&cmdbuf[5]);
1122                 }
1123
1124         else if (!strncasecmp(cmdbuf,"KFLR",4)) {
1125                 cmd_kflr(&cmdbuf[5]);
1126                 }
1127
1128         else if (!strncasecmp(cmdbuf,"EFLR",4)) {
1129                 cmd_eflr(&cmdbuf[5]);
1130                 }
1131
1132         else if (!strncasecmp(cmdbuf,"IDEN",4)) {
1133                 cmd_iden(&cmdbuf[5]);
1134                 }
1135
1136         else if (!strncasecmp(cmdbuf,"IPGM",4)) {
1137                 cmd_ipgm(&cmdbuf[5]);
1138                 }
1139
1140         else if (!strncasecmp(cmdbuf,"TERM",4)) {
1141                 cmd_term(&cmdbuf[5]);
1142                 }
1143
1144         else if (!strncasecmp(cmdbuf,"DOWN",4)) {
1145                 cmd_down();
1146                 }
1147
1148         else if (!strncasecmp(cmdbuf,"SCDN",4)) {
1149                 cmd_scdn(&cmdbuf[5]);
1150                 }
1151
1152         else if (!strncasecmp(cmdbuf, "NSET", 4)) {
1153                 cmd_nset(&cmdbuf[5]);
1154                 }
1155
1156         else if (!strncasecmp(cmdbuf, "UIMG", 4)) {
1157                 cmd_uimg(&cmdbuf[5]);
1158                 }
1159
1160         else if (!strncasecmp(cmdbuf, "TIME", 4)) {
1161                 cmd_time();
1162                 }
1163
1164         else if (!strncasecmp(cmdbuf, "AGUP", 4)) {
1165                 cmd_agup(&cmdbuf[5]);
1166                 }
1167
1168         else if (!strncasecmp(cmdbuf, "ASUP", 4)) {
1169                 cmd_asup(&cmdbuf[5]);
1170                 }
1171
1172         else if (!strncasecmp(cmdbuf, "GPEX", 4)) {
1173                 cmd_gpex(&cmdbuf[5]);
1174                 }
1175
1176         else if (!strncasecmp(cmdbuf, "SPEX", 4)) {
1177                 cmd_spex(&cmdbuf[5]);
1178                 }
1179
1180         else if (!strncasecmp(cmdbuf, "CONF", 4)) {
1181                 cmd_conf(&cmdbuf[5]);
1182                 }
1183
1184 #ifdef DEBUG_MEMORY_LEAKS
1185         else if (!strncasecmp(cmdbuf, "LEAK", 4)) {
1186                 dump_tracked();
1187                 }
1188 #endif
1189
1190         else if (!DLoader_Exec_Cmd(cmdbuf))
1191                 {
1192                    cprintf("%d Unrecognized or unsupported command.\n",
1193                             ERROR);
1194                 }
1195
1196         /* Run any after-each-command outines registered by modules */
1197         PerformSessionHooks(EVT_CMD);
1198 }