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(9, "master_startup() started\n");
  58         lprintf(7, "Opening databases\n");
  59         open_databases();
  60
  61         if (do_defrag) {
  62                 defrag_databases();
  63         }
  64
  65         check_ref_counts();
  66
  67         lprintf(7, "Creating base rooms (if necessary)\n");
  68         create_room(BASEROOM,           0, "", 0, 1);
  69         create_room(AIDEROOM,           3, "", 0, 1);
  70         create_room(SYSCONFIGROOM,      3, "", 0, 1);
  71         create_room(config.c_twitroom,  0, "", 0, 1);
  72
  73         lprintf(7, "Seeding the pseudo-random number generator...\n");
  74         gettimeofday(&tv, NULL);
  75         srand(tv.tv_usec);
  76         lprintf(9, "master_startup() finished\n");
  77 }
  78
  79
  80
  81 /*
  82  * Cleanup routine to be called when the server is shutting down.
  83  * WARNING: It's no longer safe to call this function to force a shutdown.
  84  * Instead, set time_to_die = 1.
  85  */
  86 void master_cleanup(void) {
  87         struct CleanupFunctionHook *fcn;
  88
  89         /* Run any cleanup routines registered by loadable modules */
  90         for (fcn = CleanupHookTable; fcn != NULL; fcn = fcn->next) {
  91                 (*fcn->h_function_pointer)();
  92         }
  93
  94         /* Close databases */
  95         lprintf(7, "Closing databases\n");
  96         close_databases();
  97
  98         /* Do system-dependent stuff */
  99         sysdep_master_cleanup();
 100
 101         /* Now go away. */
 102         lprintf(3, "citserver: exiting.\n");
 103         fflush(stdout); fflush(stderr);
 104         exit(0);
 105 }
 106
 107
 108 /*
 109  * Free any per-session data allocated by modules or whatever
 110  */
 111 void deallocate_user_data(struct CitContext *con)
 112 {
 113         struct CtdlSessData *ptr;
 114
 115         begin_critical_section(S_SESSION_TABLE);
 116         while (con->FirstSessData != NULL) {
 117                 lprintf(9, "Deallocating user data symbol %ld\n",
 118                         con->FirstSessData->sym_id);
 119                 if (con->FirstSessData->sym_data != NULL)
 120                         phree(con->FirstSessData->sym_data);
 121                 ptr = con->FirstSessData->next;
 122                 phree(con->FirstSessData);
 123                 con->FirstSessData = ptr;
 124         }
 125         end_critical_section(S_SESSION_TABLE);
 126 }
 127
 128
 129
 130
 131 /*
 132  * Terminate a session and remove its context data structure.
 133  */
 134 void RemoveContext (struct CitContext *con)
 135 {
 136         struct CitContext *ptr = NULL;
 137         struct CitContext *ToFree = NULL;
 138
 139         lprintf(9, "RemoveContext() called\n");
 140         if (con==NULL) {
 141                 lprintf(5, "WARNING: RemoveContext() called with NULL!\n");
 142                 return;
 143                 }
 144
 145         /* Remove the context from the global context list.  This needs
 146          * to get done FIRST to avoid concurrency problems.  It is *vitally*
 147          * important to keep num_sessions accurate!!
 148          */
 149         lprintf(7, "Removing context for session %d\n", con->cs_pid);
 150         begin_critical_section(S_SESSION_TABLE);
 151         if (ContextList == con) {
 152                 ToFree = ContextList;
 153                 ContextList = ContextList->next;
 154                 --num_sessions;
 155                 }
 156         else {
 157                 for (ptr = ContextList; ptr != NULL; ptr = ptr->next) {
 158                         if (ptr->next == con) {
 159                                 ToFree = ptr->next;
 160                                 ptr->next = ptr->next->next;
 161                                 --num_sessions;
 162                                 }
 163                         }
 164                 }
 165         end_critical_section(S_SESSION_TABLE);
 166
 167         if (ToFree == NULL) {
 168                 lprintf(9, "RemoveContext() found nothing to remove\n");
 169                 return;
 170         }
 171
 172         /* Run any cleanup routines registered by loadable modules.
 173          * Note 1: This must occur *before* deallocate_user_data() because the
 174          *         cleanup functions might touch dynamic session data.
 175          * Note 2: We have to "become_session()" because the cleanup functions
 176          *         might make references to "CC" assuming it's the right one.
 177          */
 178         become_session(con);
 179         PerformSessionHooks(EVT_STOP);
 180         become_session(NULL);
 181
 182         /* Now handle all of the administrivia. */
 183         lprintf(7, "Calling logout(%d)\n", con->cs_pid);
 184         logout(con);
 185
 186         rec_log(CL_TERMINATE, con->curr_user);
 187         unlink(con->temp);
 188         lprintf(3, "citserver[%3d]: ended.\n", con->cs_pid);
 189
 190
 191         syslog(LOG_NOTICE,"session %d: ended", con->cs_pid);
 192
 193         /* Deallocate any user-data attached to this session */
 194         deallocate_user_data(con);
 195
 196         /* If the client is still connected, blow 'em away. */
 197         lprintf(7, "Closing socket %d\n", con->client_socket);
 198         close(con->client_socket);
 199
 200     /* stu 2/7/2001 free up mem used by reader */
 201     if (con->readbuf != NULL)
 202       phree(con->readbuf);
 203
 204         /* This is where we used to check for scheduled shutdowns. */
 205
 206         /* Free up the memory used by this context */
 207         phree(con);
 208
 209         lprintf(7, "Done with RemoveContext()\n");
 210 }
 211
 212
 213
 214 /*
 215  * Get a dynamic symbol number for per-session user data.
 216  * This API call should be made only ONCE per symbol per citserver run.
 217  */
 218 int CtdlGetDynamicSymbol()
 219 {
 220         static unsigned int next_symbol = SYM_MAX;
 221         return ++next_symbol;
 222 }
 223
 224
 225
 226 /*
 227  * Return a pointer to some generic per-session user data.
 228  * (This function returns NULL if the requested symbol is not allocated.)
 229  *
 230  * NOTE: we use critical sections for allocating and de-allocating these,
 231  *       but not for locating one.
 232  */
 233 void *CtdlGetUserData(unsigned long requested_sym)
 234 {
 235         struct CtdlSessData *ptr;
 236
 237         for (ptr = CC->FirstSessData; ptr != NULL; ptr = ptr->next)
 238                 if (ptr->sym_id == requested_sym)
 239                         return(ptr->sym_data);
 240
 241         lprintf(2, "ERROR! CtdlGetUserData(%ld) symbol not allocated\n",
 242                 requested_sym);
 243         return NULL;
 244 }
 245
 246
 247 /*
 248  * Allocate some generic per-session user data.
 249  */
 250 void CtdlAllocUserData(unsigned long requested_sym, size_t num_bytes)
 251 {
 252         struct CtdlSessData *ptr;
 253
 254         lprintf(9, "CtdlAllocUserData(%ld) called\n", requested_sym);
 255
 256         /* Fail silently if the symbol is already registered. */
 257         for (ptr = CC->FirstSessData; ptr != NULL; ptr = ptr->next)  {
 258                 if (ptr->sym_id == requested_sym) {
 259                         return;
 260                 }
 261         }
 262
 263         /* Grab us some memory!  Dem's good eatin' !!  */
 264         ptr = mallok(sizeof(struct CtdlSessData));
 265         ptr->sym_id = requested_sym;
 266         ptr->sym_data = mallok(num_bytes);
 267         memset(ptr->sym_data, 0, num_bytes);
 268
 269         begin_critical_section(S_SESSION_TABLE);
 270         ptr->next = CC->FirstSessData;
 271         CC->FirstSessData = ptr;
 272         end_critical_section(S_SESSION_TABLE);
 273
 274         lprintf(9, "CtdlAllocUserData(%ld) finished\n", requested_sym);
 275 }
 276
 277
 278 /*
 279  * Change the size of a buffer allocated with CtdlAllocUserData()
 280  */
 281 void CtdlReallocUserData(unsigned long requested_sym, size_t num_bytes)
 282 {
 283         struct CtdlSessData *ptr;
 284
 285         for (ptr = CC->FirstSessData; ptr != NULL; ptr = ptr->next)  {
 286                 if (ptr->sym_id == requested_sym) {
 287                         ptr->sym_data = reallok(ptr->sym_data, num_bytes);
 288                         return;
 289                 }
 290         }
 291
 292         lprintf(2, "CtdlReallocUserData() ERROR: symbol %ld not found!\n",
 293                 requested_sym);
 294 }
 295
 296
 297
 298
 299
 300
 301 /*
 302  * cmd_info()  -  tell the client about this server
 303  */
 304 void cmd_info(void) {
 305         cprintf("%d Server info:\n", LISTING_FOLLOWS);
 306         cprintf("%d\n", CC->cs_pid);
 307         cprintf("%s\n", config.c_nodename);
 308         cprintf("%s\n", config.c_humannode);
 309         cprintf("%s\n", config.c_fqdn);
 310         cprintf("%s\n", CITADEL);
 311         cprintf("%d\n", REV_LEVEL);
 312         cprintf("%s\n", config.c_bbs_city);
 313         cprintf("%s\n", config.c_sysadm);
 314         cprintf("%d\n", SERVER_TYPE);
 315         cprintf("%s\n", config.c_moreprompt);
 316         cprintf("1\n"); /* 1 = yes, this system supports floors */
 317         cprintf("1\n"); /* 1 = we support the extended paging options */
 318         cprintf("%s\n", CC->cs_nonce);
 319         cprintf("000\n");
 320 }
 321
 322
 323 /*
 324  * returns an asterisk if there are any express messages waiting,
 325  * space otherwise.
 326  */
 327 char CtdlCheckExpress(void) {
 328         if (CC->FirstExpressMessage == NULL) {
 329                 return(' ');
 330                 }
 331         else {
 332                 return('*');
 333                 }
 334         }
 335
 336 void cmd_time(void)
 337 {
 338    time_t tv;
 339
 340    tv = time(NULL);
 341
 342    cprintf("%d %ld\n", OK, tv);
 343 }
 344
 345 /*
 346  * Check whether two hostnames match.
 347  * "Realname" should be an actual name of a client that is trying to connect;
 348  * "testname" should be the value we are comparing it with. The idea is that we
 349  * want to compare with both the abbreviated and fully-qualified versions of
 350  * "testname;" some people define "localhost" as "localhost.foo.com," etc.
 351  */
 352 static int hostnames_match(const char *realname, const char *testname) {
 353         struct hostent *he;
 354         int retval = 0;
 355
 356         if (!strcasecmp(realname, testname))
 357                 return 1;
 358
 359 #ifdef HAVE_NONREENTRANT_NETDB
 360         begin_critical_section(S_NETDB);
 361 #endif
 362
 363         if ((he = gethostbyname(testname)) != NULL)
 364                 if (!strcasecmp(realname, he->h_name))
 365                         retval = 1;
 366
 367 #ifdef HAVE_NONREENTRANT_NETDB
 368         end_critical_section(S_NETDB);
 369 #endif
 370
 371         return retval;
 372         }
 373
 374 /*
 375  * check a hostname against the public_clients file
 376  */
 377 int is_public_client(char *where)
 378 {
 379         char buf[SIZ];
 380         FILE *fp;
 381
 382         lprintf(9, "Checking whether %s is a public client\n", where);
 383
 384         if (hostnames_match(where, "localhost")) return(1);
 385         if (hostnames_match(where, config.c_fqdn)) return(1);
 386
 387         fp = fopen("public_clients","r");
 388         if (fp == NULL) return(0);
 389
 390         while (fgets(buf, sizeof buf, fp)!=NULL) {
 391                 while (isspace((buf[strlen(buf)-1])))
 392                         buf[strlen(buf)-1] = 0;
 393                 if (hostnames_match(where,buf)) {
 394                         fclose(fp);
 395                         return(1);
 396                         }
 397                 }
 398
 399         fclose(fp);
 400         return(0);
 401         }
 402
 403
 404 /*
 405  * the client is identifying itself to the server
 406  */
 407 void cmd_iden(char *argbuf)
 408 {
 409         int dev_code;
 410         int cli_code;
 411         int rev_level;
 412         char desc[SIZ];
 413         char from_host[SIZ];
 414         struct in_addr addr;
 415         int do_lookup = 0;
 416
 417         if (num_parms(argbuf)<4) {
 418                 cprintf("%d usage error\n",ERROR);
 419                 return;
 420         }
 421
 422         dev_code = extract_int(argbuf,0);
 423         cli_code = extract_int(argbuf,1);
 424         rev_level = extract_int(argbuf,2);
 425         extract(desc,argbuf,3);
 426
 427         safestrncpy(from_host, config.c_fqdn, sizeof from_host);
 428         from_host[sizeof from_host - 1] = 0;
 429         if (num_parms(argbuf)>=5) extract(from_host,argbuf,4);
 430
 431         CC->cs_clientdev = dev_code;
 432         CC->cs_clienttyp = cli_code;
 433         CC->cs_clientver = rev_level;
 434         safestrncpy(CC->cs_clientname, desc, sizeof CC->cs_clientname);
 435         CC->cs_clientname[31] = 0;
 436
 437         if (strlen(from_host) > 0) {
 438                 if (CC->is_local_socket) do_lookup = 1;
 439                 else if (is_public_client(CC->cs_host)) do_lookup = 1;
 440         }
 441
 442         if (do_lookup) {
 443                 lprintf(9, "Looking up hostname '%s'\n", from_host);
 444                 if ((addr.s_addr = inet_addr(from_host)) != -1) {
 445                         locate_host(CC->cs_host, &addr);
 446                 }
 447                 else {
 448                         safestrncpy(CC->cs_host, from_host, sizeof CC->cs_host);
 449                         CC->cs_host[24] = 0;
 450                 }
 451         }
 452
 453         lprintf(7, "client %d/%d/%01d.%02d (%s)\n",
 454                 dev_code,
 455                 cli_code,
 456                 (rev_level / 100),
 457                 (rev_level % 100),
 458                 desc);
 459
 460         syslog(LOG_NOTICE,"session %d: client %d/%d/%01d.%02d (%s) from %s\n",
 461                 CC->cs_pid,
 462                 dev_code,
 463                 cli_code,
 464                 (rev_level / 100),
 465                 (rev_level % 100),
 466                 desc,
 467                 CC->cs_host);
 468         cprintf("%d Ok\n",OK);
 469 }
 470
 471
 472 /*
 473  * display system messages or help
 474  */
 475 void cmd_mesg(char *mname)
 476 {
 477         FILE *mfp;
 478         char targ[SIZ];
 479         char buf[SIZ];
 480         char *dirs[2];
 481
 482         extract(buf,mname,0);
 483
 484
 485         dirs[0]=mallok(64);
 486         dirs[1]=mallok(64);
 487         strcpy(dirs[0],"messages");
 488         strcpy(dirs[1],"help");
 489         mesg_locate(targ,buf,2,dirs);
 490         phree(dirs[0]);
 491         phree(dirs[1]);
 492
 493
 494         if (strlen(targ)==0) {
 495                 cprintf("%d '%s' not found.\n",ERROR,mname);
 496                 return;
 497                 }
 498
 499         mfp = fopen(targ,"r");
 500         if (mfp==NULL) {
 501                 cprintf("%d Cannot open '%s': %s\n",
 502                         ERROR,targ,strerror(errno));
 503                 return;
 504                 }
 505         cprintf("%d %s\n",LISTING_FOLLOWS,buf);
 506
 507         while (fgets(buf, (SIZ-1), mfp)!=NULL) {
 508                 buf[strlen(buf)-1] = 0;
 509                 do_help_subst(buf);
 510                 cprintf("%s\n",buf);
 511                 }
 512
 513         fclose(mfp);
 514         cprintf("000\n");
 515         }
 516
 517
 518 /*
 519  * enter system messages or help
 520  */
 521 void cmd_emsg(char *mname)
 522 {
 523         FILE *mfp;
 524         char targ[SIZ];
 525         char buf[SIZ];
 526         char *ibuf;
 527         char *dirs[2];
 528         int a;
 529
 530         if (CtdlAccessCheck(ac_aide)) return;
 531
 532         extract(buf,mname,0);
 533         for (a=0; a<strlen(buf); ++a) {         /* security measure */
 534                 if (buf[a] == '/') buf[a] = '.';
 535                 }
 536
 537         dirs[0]=mallok(64);
 538         dirs[1]=mallok(64);
 539         strcpy(dirs[0],"messages");
 540         strcpy(dirs[1],"help");
 541         mesg_locate(targ,buf,2,dirs);
 542         phree(dirs[0]);
 543         phree(dirs[1]);
 544
 545         if (strlen(targ)==0) {
 546                 snprintf(targ, sizeof targ, "./help/%s", buf);
 547                 }
 548
 549         mfp = fopen(targ,"w");
 550         if (mfp==NULL) {
 551                 cprintf("%d Cannot open '%s': %s\n",
 552                         ERROR,targ,strerror(errno));
 553                 return;
 554                 }
 555         cprintf("%d %s\n", SEND_LISTING, targ);
 556
 557         while (client_gets(&ibuf), strcmp(ibuf, "000")) {
 558                 fprintf(mfp, "%s\n", ibuf);
 559                 }
 560
 561         fclose(mfp);
 562         }
 563
 564
 565 /* Don't show the names of private rooms unless the viewing
 566  * user also knows the rooms.
 567  */
 568 void GenerateRoomDisplay(char *real_room,
 569                         struct CitContext *viewed,
 570                         struct CitContext *viewer) {
 571
 572         strcpy(real_room, viewed->quickroom.QRname);
 573         if (viewed->quickroom.QRflags & QR_MAILBOX) {
 574                 strcpy(real_room, &real_room[11]);
 575         }
 576         if (viewed->quickroom.QRflags & QR_PRIVATE) {
 577                 if ( (CtdlRoomAccess(&viewed->quickroom, &viewer->usersupp)
 578                    & UA_KNOWN) == 0) {
 579                         strcpy(real_room, "<private room>");
 580                 }
 581         }
 582
 583         if (viewed->cs_flags & CS_CHAT) {
 584                 while (strlen(real_room) < 14)
 585                         strcat(real_room, " ");
 586
 587                 strcpy(&real_room[14], "<chat>");
 588         }
 589
 590 }
 591
 592 /*
 593  * Convenience function.
 594  */
 595 int CtdlAccessCheck(int required_level) {
 596
 597         if (CC->internal_pgm) return(0);
 598         if (required_level >= ac_internal) {
 599                 cprintf("%d This is not a user-level command.\n",
 600                         ERROR+HIGHER_ACCESS_REQUIRED);
 601                 return(-1);
 602         }
 603
 604         if (CC->usersupp.axlevel >= 6) return(0);
 605         if (required_level >= ac_aide) {
 606                 cprintf("%d This command requires Aide access.\n",
 607                         ERROR+HIGHER_ACCESS_REQUIRED);
 608                 return(-1);
 609         }
 610
 611         if (is_room_aide()) return(0);
 612         if (required_level >= ac_room_aide) {
 613                 cprintf("%d This command requires Aide or Room Aide access.\n",
 614                         ERROR + HIGHER_ACCESS_REQUIRED);
 615                 return(-1);
 616         }
 617
 618         if (CC->logged_in) return(0);
 619         if (required_level >= ac_logged_in) {
 620                 cprintf("%d Not logged in.\n", ERROR+NOT_LOGGED_IN);
 621                 return(-1);
 622         }
 623
 624         /* shhh ... succeed quietly */
 625         return(0);
 626 }
 627
 628
 629
 630 /*
 631  * Terminate another running session
 632  */
 633 void cmd_term(char *cmdbuf)
 634 {
 635         int session_num;
 636         struct CitContext *ccptr;
 637         int found_it = 0;
 638
 639         if (CtdlAccessCheck(ac_aide)) return;
 640
 641         session_num = extract_int(cmdbuf, 0);
 642         if (session_num == CC->cs_pid) {
 643                 cprintf("%d You can't kill your own session.\n", ERROR);
 644                 return;
 645                 }
 646
 647         lprintf(9, "Locating session to kill\n");
 648         begin_critical_section(S_SESSION_TABLE);
 649         for (ccptr = ContextList; ccptr != NULL; ccptr = ccptr->next) {
 650                 if (session_num == ccptr->cs_pid) {
 651                         ccptr->kill_me = 1;
 652                         found_it = 1;
 653                         }
 654                 }
 655         end_critical_section(S_SESSION_TABLE);
 656
 657         if (found_it) {
 658                 cprintf("%d Session terminated.\n", OK);
 659                 }
 660         else {
 661                 cprintf("%d No such session.\n", ERROR);
 662                 }
 663         }
 664
 665
 666
 667
 668
 669 /*
 670  * get the paginator prompt
 671  */
 672 void cmd_more(void) {
 673         cprintf("%d %s\n",OK,config.c_moreprompt);
 674         }
 675
 676 /*
 677  * echo
 678  */
 679 void cmd_echo(char *etext)
 680 {
 681         cprintf("%d %s\n",OK,etext);
 682         }
 683
 684
 685
 686 /*
 687  * identify as internal program
 688  */
 689 void cmd_ipgm(char *argbuf)
 690 {
 691         int secret;
 692
 693         secret = extract_int(argbuf, 0);
 694         if (secret == config.c_ipgm_secret) {
 695                 CC->internal_pgm = 1;
 696                 strcpy(CC->curr_user, "<internal program>");
 697                 CC->cs_flags = CC->cs_flags|CS_STEALTH;
 698                 cprintf("%d Authenticated as an internal program.\n",OK);
 699                 }
 700         else {
 701                 cprintf("%d Authentication failed.\n",ERROR);
 702                 lprintf(3, "Warning: ipgm authentication failed.\n");
 703                 }
 704         }
 705
 706
 707 /*
 708  * Shut down the server
 709  */
 710 void cmd_down(void) {
 711
 712         if (CtdlAccessCheck(ac_aide)) return;
 713
 714         cprintf("%d Shutting down server.  Goodbye.\n", OK);
 715         time_to_die = 1;
 716         }
 717
 718 /*
 719  * Schedule or cancel a server shutdown
 720  */
 721 void cmd_scdn(char *argbuf)
 722 {
 723         int new_state;
 724
 725         if (CtdlAccessCheck(ac_aide)) return;
 726
 727         new_state = extract_int(argbuf, 0);
 728         if ((new_state == 0) || (new_state == 1)) {
 729                 ScheduledShutdown = new_state;
 730                 }
 731         cprintf("%d %d\n", OK, ScheduledShutdown);
 732 }
 733
 734
 735 /*
 736  * Set or unset asynchronous protocol mode
 737  */
 738 void cmd_asyn(char *argbuf)
 739 {
 740         int new_state;
 741
 742         new_state = extract_int(argbuf, 0);
 743         if ((new_state == 0) || (new_state == 1)) {
 744                 CC->is_async = new_state;
 745         }
 746         cprintf("%d %d\n", OK, CC->is_async);
 747 }
 748
 749
 750 /*
 751  * Generate a "nonce" for APOP-style authentication.
 752  *
 753  * RFC 1725 et al specify a PID to be placed in front of the nonce.
 754  * Quoth BTX: That would be stupid.
 755  */
 756 void generate_nonce(struct CitContext *con) {
 757         struct timeval tv;
 758
 759         memset(con->cs_nonce, NONCE_SIZE, 0);
 760         gettimeofday(&tv, NULL);
 761         memset(con->cs_nonce, NONCE_SIZE, 0);
 762         snprintf(con->cs_nonce, NONCE_SIZE, "<%d%ld@%s>",
 763                 rand(), tv.tv_usec, config.c_fqdn);
 764 }
 765
 766
 767
 768
 769 /*
 770  * Back-end function for starting a session
 771  */
 772 void begin_session(struct CitContext *con)
 773 {
 774         int len;
 775         struct sockaddr_in sin;
 776
 777         /*
 778          * Initialize some variables specific to our context.
 779          */
 780         con->logged_in = 0;
 781         con->internal_pgm = 0;
 782         con->download_fp = NULL;
 783         con->upload_fp = NULL;
 784         con->FirstExpressMessage = NULL;
 785         time(&con->lastcmd);
 786         time(&con->lastidle);
 787         strcpy(con->lastcmdname, "    ");
 788         strcpy(con->cs_clientname, "(unknown)");
 789         strcpy(con->curr_user, NLI);
 790         strcpy(con->net_node,"");
 791         strcpy(con->fake_username, "");
 792         strcpy(con->fake_postname, "");
 793         strcpy(con->fake_hostname, "");
 794         strcpy(con->fake_roomname, "");
 795         generate_nonce(con);
 796         snprintf(con->temp, sizeof con->temp, tmpnam(NULL));
 797         safestrncpy(con->cs_host, config.c_fqdn, sizeof con->cs_host);
 798         con->cs_host[sizeof con->cs_host - 1] = 0;
 799         len = sizeof sin;
 800         if (!CC->is_local_socket) {
 801                 if (!getpeername(con->client_socket,
 802                    (struct sockaddr *) &sin, &len))
 803                         locate_host(con->cs_host, &sin.sin_addr);
 804         }
 805         else {
 806                 strcpy(con->cs_host, "");
 807         }
 808         con->cs_flags = 0;
 809         con->upload_type = UPL_FILE;
 810         con->dl_is_net = 0;
 811         con->FirstSessData = NULL;
 812
 813         con->nologin = 0;
 814         if ((config.c_maxsessions > 0)&&(num_sessions > config.c_maxsessions))
 815                 con->nologin = 1;
 816
 817         lprintf(3, "citserver[%3d]: started.\n", con->cs_pid);
 818
 819         /* Run any session startup routines registered by loadable modules */
 820         PerformSessionHooks(EVT_START);
 821
 822         rec_log(CL_CONNECT, "");
 823 }
 824
 825
 826 void citproto_begin_session() {
 827         if (CC->nologin==1) {
 828                 cprintf("%d %s: Too many users are already online "
 829                         "(maximum is %d)\n",
 830                         ERROR+MAX_SESSIONS_EXCEEDED,
 831                         config.c_nodename, config.c_maxsessions);
 832                 }
 833         else {
 834                 cprintf("%d %s Citadel/UX server ready.\n",
 835                         OK, config.c_nodename);
 836                 }
 837 }
 838
 839
 840
 841
 842 /*
 843  * This loop recognizes all server commands.
 844  */
 845 void do_command_loop(void) {
 846 /*      char cmdbuf[SIZ]; stu */
 847         char *icmdbuf;
 848
 849         time(&CC->lastcmd);
 850 /*      memset(cmdbuf, 0, sizeof cmdbuf); */ /* Clear it, just in case */
 851         if (client_gets(&icmdbuf) < 1) {
 852                 lprintf(3, "Client socket is broken.  Ending session.\n");
 853                 CC->kill_me = 1;
 854                 return;
 855         }
 856         lprintf(5, "citserver[%3d]: %s\n", CC->cs_pid, icmdbuf);
 857
 858         /*
 859          * Let other clients see the last command we executed, and
 860          * update the idle time, but not NOOP, PEXP, or GEXP.
 861          */
 862         if ( (strncasecmp(icmdbuf, "NOOP", 4))
 863            && (strncasecmp(icmdbuf, "PEXP", 4))
 864            && (strncasecmp(icmdbuf, "GEXP", 4)) ) {
 865                 strcpy(CC->lastcmdname, "    ");
 866                 safestrncpy(CC->lastcmdname, icmdbuf,
 867                         sizeof(CC->lastcmdname) );
 868                 time(&CC->lastidle);
 869                 }
 870
 871         if ((strncasecmp(icmdbuf, "ENT0", 4))
 872            && (strncasecmp(icmdbuf, "MESG", 4))
 873            && (strncasecmp(icmdbuf, "MSGS", 4)))
 874         {
 875            CC->cs_flags &= ~CS_POSTING;
 876         }
 877
 878         if (!strncasecmp(icmdbuf,"NOOP",4)) {
 879                 cprintf("%d%cok\n",OK,CtdlCheckExpress());
 880                 }
 881
 882         else if (!strncasecmp(icmdbuf,"QUIT",4)) {
 883                 cprintf("%d Goodbye.\n",OK);
 884                 CC->kill_me = 1;
 885                 }
 886
 887         else if (!strncasecmp(icmdbuf,"ASYN",4)) {
 888                 cmd_asyn(&icmdbuf[5]);
 889                 }
 890
 891         else if (!strncasecmp(icmdbuf,"LOUT",4)) {
 892                 if (CC->logged_in) logout(CC);
 893                 cprintf("%d logged out.\n",OK);
 894                 }
 895
 896         else if (!strncasecmp(icmdbuf,"USER",4)) {
 897                 cmd_user(&icmdbuf[5]);
 898                 }
 899
 900         else if (!strncasecmp(icmdbuf,"PASS",4)) {
 901                 cmd_pass(&icmdbuf[5]);
 902                 }
 903
 904         else if (!strncasecmp(icmdbuf,"NEWU",4)) {
 905                 cmd_newu(&icmdbuf[5]);
 906                 }
 907
 908         else if (!strncasecmp(icmdbuf,"SETP",4)) {
 909                 cmd_setp(&icmdbuf[5]);
 910                 }
 911
 912         else if (!strncasecmp(icmdbuf,"LRMS",4)) {
 913                 cmd_lrms(&icmdbuf[5]);
 914                 }
 915
 916         else if (!strncasecmp(icmdbuf,"LKRA",4)) {
 917                 cmd_lkra(&icmdbuf[5]);
 918                 }
 919
 920         else if (!strncasecmp(icmdbuf,"LKRN",4)) {
 921                 cmd_lkrn(&icmdbuf[5]);
 922                 }
 923
 924         else if (!strncasecmp(icmdbuf,"LKRO",4)) {
 925                 cmd_lkro(&icmdbuf[5]);
 926                 }
 927
 928         else if (!strncasecmp(icmdbuf,"LZRM",4)) {
 929                 cmd_lzrm(&icmdbuf[5]);
 930                 }
 931
 932         else if (!strncasecmp(icmdbuf,"GETU",4)) {
 933                 cmd_getu();
 934                 }
 935
 936         else if (!strncasecmp(icmdbuf,"SETU",4)) {
 937                 cmd_setu(&icmdbuf[5]);
 938                 }
 939
 940         else if (!strncasecmp(icmdbuf,"GOTO",4)) {
 941                 cmd_goto(&icmdbuf[5]);
 942                 }
 943
 944         else if (!strncasecmp(icmdbuf,"MSGS",4)) {
 945                 cmd_msgs(&icmdbuf[5]);
 946                 }
 947
 948         else if (!strncasecmp(icmdbuf,"WHOK",4)) {
 949                 cmd_whok();
 950                 }
 951
 952         else if (!strncasecmp(icmdbuf,"RDIR",4)) {
 953                 cmd_rdir();
 954                 }
 955
 956         else if (!strncasecmp(icmdbuf,"MSG0",4)) {
 957                 cmd_msg0(&icmdbuf[5]);
 958                 }
 959
 960         else if (!strncasecmp(icmdbuf,"MSG2",4)) {
 961                 cmd_msg2(&icmdbuf[5]);
 962                 }
 963
 964         else if (!strncasecmp(icmdbuf,"MSG3",4)) {
 965                 cmd_msg3(&icmdbuf[5]);
 966                 }
 967
 968         else if (!strncasecmp(icmdbuf,"MSG4",4)) {
 969                 cmd_msg4(&icmdbuf[5]);
 970                 }
 971
 972         else if (!strncasecmp(icmdbuf,"OPNA",4)) {
 973                 cmd_opna(&icmdbuf[5]);
 974                 }
 975
 976         else if (!strncasecmp(icmdbuf,"INFO",4)) {
 977                 cmd_info();
 978                 }
 979
 980         else if (!strncasecmp(icmdbuf,"SLRP",4)) {
 981                 cmd_slrp(&icmdbuf[5]);
 982                 }
 983
 984         else if (!strncasecmp(icmdbuf,"INVT",4)) {
 985                 cmd_invt_kick(&icmdbuf[5],1);
 986                 }
 987
 988         else if (!strncasecmp(icmdbuf,"KICK",4)) {
 989                 cmd_invt_kick(&icmdbuf[5],0);
 990                 }
 991
 992         else if (!strncasecmp(icmdbuf,"GETR",4)) {
 993                 cmd_getr();
 994                 }
 995
 996         else if (!strncasecmp(icmdbuf,"SETR",4)) {
 997                 cmd_setr(&icmdbuf[5]);
 998                 }
 999
1000         else if (!strncasecmp(icmdbuf,"GETA",4)) {
1001                 cmd_geta();
1002                 }
1003
1004         else if (!strncasecmp(icmdbuf,"SETA",4)) {
1005                 cmd_seta(&icmdbuf[5]);
1006                 }
1007
1008         else if (!strncasecmp(icmdbuf,"ENT0",4)) {
1009                 cmd_ent0(&icmdbuf[5]);
1010                 }
1011
1012         else if (!strncasecmp(icmdbuf,"ENT3",4)) {
1013                 cmd_ent3(&icmdbuf[5]);
1014                 }
1015
1016         else if (!strncasecmp(icmdbuf,"RINF",4)) {
1017                 cmd_rinf();
1018                 }
1019
1020         else if (!strncasecmp(icmdbuf,"DELE",4)) {
1021                 cmd_dele(&icmdbuf[5]);
1022                 }
1023
1024         else if (!strncasecmp(icmdbuf,"KILL",4)) {
1025                 cmd_kill(&icmdbuf[5]);
1026                 }
1027
1028         else if (!strncasecmp(icmdbuf,"CRE8",4)) {
1029                 cmd_cre8(&icmdbuf[5]);
1030                 }
1031
1032         else if (!strncasecmp(icmdbuf,"MOVE",4)) {
1033                 cmd_move(&icmdbuf[5]);
1034                 }
1035
1036         else if (!strncasecmp(icmdbuf,"FORG",4)) {
1037                 cmd_forg();
1038                 }
1039
1040         else if (!strncasecmp(icmdbuf,"MESG",4)) {
1041                 cmd_mesg(&icmdbuf[5]);
1042                 }
1043
1044         else if (!strncasecmp(icmdbuf,"EMSG",4)) {
1045                 cmd_emsg(&icmdbuf[5]);
1046                 }
1047
1048         else if (!strncasecmp(icmdbuf,"GNUR",4)) {
1049                 cmd_gnur();
1050                 }
1051
1052         else if (!strncasecmp(icmdbuf,"VALI",4)) {
1053                 cmd_vali(&icmdbuf[5]);
1054                 }
1055
1056         else if (!strncasecmp(icmdbuf,"EINF",4)) {
1057                 cmd_einf(&icmdbuf[5]);
1058                 }
1059
1060         else if (!strncasecmp(icmdbuf,"LIST",4)) {
1061                 cmd_list();
1062                 }
1063
1064         else if (!strncasecmp(icmdbuf,"CHEK",4)) {
1065                 cmd_chek();
1066                 }
1067
1068         else if (!strncasecmp(icmdbuf,"DELF",4)) {
1069                 cmd_delf(&icmdbuf[5]);
1070                 }
1071
1072         else if (!strncasecmp(icmdbuf,"MOVF",4)) {
1073                 cmd_movf(&icmdbuf[5]);
1074                 }
1075
1076         else if (!strncasecmp(icmdbuf,"NETF",4)) {
1077                 cmd_netf(&icmdbuf[5]);
1078                 }
1079
1080         else if (!strncasecmp(icmdbuf,"OPEN",4)) {
1081                 cmd_open(&icmdbuf[5]);
1082                 }
1083
1084         else if (!strncasecmp(icmdbuf,"CLOS",4)) {
1085                 cmd_clos();
1086                 }
1087
1088         else if (!strncasecmp(icmdbuf,"UOPN",4)) {
1089                 cmd_uopn(&icmdbuf[5]);
1090                 }
1091
1092         else if (!strncasecmp(icmdbuf,"UCLS",4)) {
1093                 cmd_ucls(&icmdbuf[5]);
1094                 }
1095
1096         else if (!strncasecmp(icmdbuf,"READ",4)) {
1097                 cmd_read(&icmdbuf[5]);
1098                 }
1099
1100         else if (!strncasecmp(icmdbuf,"WRIT",4)) {
1101                 cmd_writ(&icmdbuf[5]);
1102                 }
1103
1104         else if (!strncasecmp(icmdbuf,"QUSR",4)) {
1105                 cmd_qusr(&icmdbuf[5]);
1106                 }
1107
1108         else if (!strncasecmp(icmdbuf,"ECHO",4)) {
1109                 cmd_echo(&icmdbuf[5]);
1110                 }
1111
1112         else if (!strncasecmp(icmdbuf,"OIMG",4)) {
1113                 cmd_oimg(&icmdbuf[5]);
1114                 }
1115
1116         else if (!strncasecmp(icmdbuf,"MORE",4)) {
1117                 cmd_more();
1118                 }
1119
1120         else if (!strncasecmp(icmdbuf,"NETP",4)) {
1121                 cmd_netp(&icmdbuf[5]);
1122                 }
1123
1124         else if (!strncasecmp(icmdbuf,"NDOP",4)) {
1125                 cmd_ndop(&icmdbuf[5]);
1126                 }
1127
1128         else if (!strncasecmp(icmdbuf,"NUOP",4)) {
1129                 cmd_nuop(&icmdbuf[5]);
1130                 }
1131
1132         else if (!strncasecmp(icmdbuf,"LFLR",4)) {
1133                 cmd_lflr();
1134                 }
1135
1136         else if (!strncasecmp(icmdbuf,"CFLR",4)) {
1137                 cmd_cflr(&icmdbuf[5]);
1138                 }
1139
1140         else if (!strncasecmp(icmdbuf,"KFLR",4)) {
1141                 cmd_kflr(&icmdbuf[5]);
1142                 }
1143
1144         else if (!strncasecmp(icmdbuf,"EFLR",4)) {
1145                 cmd_eflr(&icmdbuf[5]);
1146                 }
1147
1148         else if (!strncasecmp(icmdbuf,"IDEN",4)) {
1149                 cmd_iden(&icmdbuf[5]);
1150                 }
1151
1152         else if (!strncasecmp(icmdbuf,"IPGM",4)) {
1153                 cmd_ipgm(&icmdbuf[5]);
1154                 }
1155
1156         else if (!strncasecmp(icmdbuf,"TERM",4)) {
1157                 cmd_term(&icmdbuf[5]);
1158                 }
1159
1160         else if (!strncasecmp(icmdbuf,"DOWN",4)) {
1161                 cmd_down();
1162                 }
1163
1164         else if (!strncasecmp(icmdbuf,"SCDN",4)) {
1165                 cmd_scdn(&icmdbuf[5]);
1166                 }
1167
1168         else if (!strncasecmp(icmdbuf, "NSET", 4)) {
1169                 cmd_nset(&icmdbuf[5]);
1170                 }
1171
1172         else if (!strncasecmp(icmdbuf, "UIMG", 4)) {
1173                 cmd_uimg(&icmdbuf[5]);
1174                 }
1175
1176         else if (!strncasecmp(icmdbuf, "TIME", 4)) {
1177                 cmd_time();
1178                 }
1179
1180         else if (!strncasecmp(icmdbuf, "AGUP", 4)) {
1181                 cmd_agup(&icmdbuf[5]);
1182                 }
1183
1184         else if (!strncasecmp(icmdbuf, "ASUP", 4)) {
1185                 cmd_asup(&icmdbuf[5]);
1186                 }
1187
1188         else if (!strncasecmp(icmdbuf, "GPEX", 4)) {
1189                 cmd_gpex(&icmdbuf[5]);
1190                 }
1191
1192         else if (!strncasecmp(icmdbuf, "SPEX", 4)) {
1193                 cmd_spex(&icmdbuf[5]);
1194                 }
1195
1196         else if (!strncasecmp(icmdbuf, "CONF", 4)) {
1197                 cmd_conf(&icmdbuf[5]);
1198                 }
1199
1200 #ifdef DEBUG_MEMORY_LEAKS
1201         else if (!strncasecmp(icmdbuf, "LEAK", 4)) {
1202                 dump_tracked();
1203                 }
1204 #endif
1205
1206         else if (!DLoader_Exec_Cmd(icmdbuf))
1207                 {
1208                    cprintf("%d Unrecognized or unsupported command.\n",
1209                             ERROR);
1210                 }
1211
1212         /* Run any after-each-command outines registered by modules */
1213         PerformSessionHooks(EVT_CMD);
1214 }