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 struct CitContext *ContextList = NULL;
  61 char *unique_session_numbers;
  62 int ScheduledShutdown = 0;
  63 int do_defrag = 0;
  64
  65 /*
  66  * Various things that need to be initialized at startup
  67  */
  68 void master_startup(void) {
  69         struct timeval tv;
  70
  71         lprintf(9, "master_startup() started\n");
  72         lprintf(7, "Opening databases\n");
  73         open_databases();
  74
  75         if (do_defrag) {
  76                 defrag_databases();
  77         }
  78
  79         check_ref_counts();
  80
  81         lprintf(7, "Creating base rooms (if necessary)\n");
  82         create_room(BASEROOM,           0, "", 0, 1);
  83         create_room(AIDEROOM,           3, "", 0, 1);
  84         create_room(SYSCONFIGROOM,      3, "", 0, 1);
  85         create_room(config.c_twitroom,  0, "", 0, 1);
  86
  87         lprintf(7, "Seeding the pseudo-random number generator...\n");
  88         gettimeofday(&tv, NULL);
  89         srand(tv.tv_usec);
  90         lprintf(9, "master_startup() finished\n");
  91 }
  92
  93
  94
  95 /*
  96  * Cleanup routine to be called when the server is shutting down.
  97  * WARNING: It's no longer safe to call this function to force a shutdown.
  98  * Instead, set time_to_die = 1.
  99  */
 100 void master_cleanup(void) {
 101         struct CleanupFunctionHook *fcn;
 102
 103         /* Run any cleanup routines registered by loadable modules */
 104         for (fcn = CleanupHookTable; fcn != NULL; fcn = fcn->next) {
 105                 (*fcn->h_function_pointer)();
 106         }
 107
 108         /* Close databases */
 109         lprintf(7, "Closing databases\n");
 110         close_databases();
 111
 112         /* Do system-dependent stuff */
 113         sysdep_master_cleanup();
 114
 115         /* Now go away. */
 116         lprintf(3, "citserver: exiting.\n");
 117         fflush(stdout); fflush(stderr);
 118         exit(0);
 119 }
 120
 121
 122 /*
 123  * Free any per-session data allocated by modules or whatever
 124  */
 125 void deallocate_user_data(struct CitContext *con)
 126 {
 127         struct CtdlSessData *ptr;
 128
 129         begin_critical_section(S_SESSION_TABLE);
 130         while (con->FirstSessData != NULL) {
 131                 lprintf(9, "Deallocating user data symbol %ld\n",
 132                         con->FirstSessData->sym_id);
 133                 if (con->FirstSessData->sym_data != NULL)
 134                         phree(con->FirstSessData->sym_data);
 135                 ptr = con->FirstSessData->next;
 136                 phree(con->FirstSessData);
 137                 con->FirstSessData = ptr;
 138         }
 139         end_critical_section(S_SESSION_TABLE);
 140 }
 141
 142
 143
 144
 145 /*
 146  * Terminate a session and remove its context data structure.
 147  */
 148 void RemoveContext (struct CitContext *con)
 149 {
 150         struct CitContext *ptr = NULL;
 151         struct CitContext *ToFree = NULL;
 152
 153         lprintf(9, "RemoveContext() called\n");
 154         if (con==NULL) {
 155                 lprintf(5, "WARNING: RemoveContext() called with NULL!\n");
 156                 return;
 157                 }
 158
 159         /* Remove the context from the global context list.  This needs
 160          * to get done FIRST to avoid concurrency problems.  It is *vitally*
 161          * important to keep num_sessions accurate!!
 162          */
 163         lprintf(7, "Removing context for session %d\n", con->cs_pid);
 164         begin_critical_section(S_SESSION_TABLE);
 165         if (ContextList == con) {
 166                 ToFree = ContextList;
 167                 ContextList = ContextList->next;
 168                 --num_sessions;
 169                 }
 170         else {
 171                 for (ptr = ContextList; ptr != NULL; ptr = ptr->next) {
 172                         if (ptr->next == con) {
 173                                 ToFree = ptr->next;
 174                                 ptr->next = ptr->next->next;
 175                                 --num_sessions;
 176                                 }
 177                         }
 178                 }
 179         end_critical_section(S_SESSION_TABLE);
 180
 181         if (ToFree == NULL) {
 182                 lprintf(9, "RemoveContext() found nothing to remove\n");
 183                 return;
 184         }
 185
 186         /* Run any cleanup routines registered by loadable modules.
 187          * Note 1: This must occur *before* deallocate_user_data() because the
 188          *         cleanup functions might touch dynamic session data.
 189          * Note 2: We have to "become_session()" because the cleanup functions
 190          *         might make references to "CC" assuming it's the right one.
 191          */
 192         become_session(con);
 193         PerformSessionHooks(EVT_STOP);
 194         become_session(NULL);
 195
 196         /* Now handle all of the administrivia. */
 197         lprintf(7, "Calling logout(%d)\n", con->cs_pid);
 198         logout(con);
 199
 200         rec_log(CL_TERMINATE, con->curr_user);
 201         unlink(con->temp);
 202         lprintf(3, "citserver[%3d]: ended.\n", con->cs_pid);
 203
 204
 205         syslog(LOG_NOTICE,"session %d: ended", con->cs_pid);
 206
 207         /* Deallocate any user-data attached to this session */
 208         deallocate_user_data(con);
 209
 210         /* If the client is still connected, blow 'em away. */
 211         lprintf(7, "Closing socket %d\n", con->client_socket);
 212         close(con->client_socket);
 213
 214         /* This is where we used to check for scheduled shutdowns. */
 215
 216         /* Free up the memory used by this context */
 217         phree(con);
 218
 219         lprintf(7, "Done with RemoveContext()\n");
 220 }
 221
 222
 223
 224 /*
 225  * Get a dynamic symbol number for per-session user data.
 226  * This API call should be made only ONCE per symbol per citserver run.
 227  */
 228 int CtdlGetDynamicSymbol()
 229 {
 230         static unsigned int next_symbol = SYM_MAX;
 231         return ++next_symbol;
 232 }
 233
 234
 235
 236 /*
 237  * Return a pointer to some generic per-session user data.
 238  * (This function returns NULL if the requested symbol is not allocated.)
 239  *
 240  * NOTE: we use critical sections for allocating and de-allocating these,
 241  *       but not for locating one.
 242  */
 243 void *CtdlGetUserData(unsigned long requested_sym)
 244 {
 245         struct CtdlSessData *ptr;
 246
 247         for (ptr = CC->FirstSessData; ptr != NULL; ptr = ptr->next)
 248                 if (ptr->sym_id == requested_sym)
 249                         return(ptr->sym_data);
 250
 251         lprintf(2, "ERROR! CtdlGetUserData(%ld) symbol not allocated\n",
 252                 requested_sym);
 253         return NULL;
 254 }
 255
 256
 257 /*
 258  * Allocate some generic per-session user data.
 259  */
 260 void CtdlAllocUserData(unsigned long requested_sym, size_t num_bytes)
 261 {
 262         struct CtdlSessData *ptr;
 263
 264         lprintf(9, "CtdlAllocUserData(%ld) called\n", requested_sym);
 265
 266         /* Fail silently if the symbol is already registered. */
 267         for (ptr = CC->FirstSessData; ptr != NULL; ptr = ptr->next)  {
 268                 if (ptr->sym_id == requested_sym) {
 269                         return;
 270                 }
 271         }
 272
 273         /* Grab us some memory!  Dem's good eatin' !!  */
 274         ptr = mallok(sizeof(struct CtdlSessData));
 275         ptr->sym_id = requested_sym;
 276         ptr->sym_data = mallok(num_bytes);
 277         memset(ptr->sym_data, 0, num_bytes);
 278
 279         begin_critical_section(S_SESSION_TABLE);
 280         ptr->next = CC->FirstSessData;
 281         CC->FirstSessData = ptr;
 282         end_critical_section(S_SESSION_TABLE);
 283
 284         lprintf(9, "CtdlAllocUserData(%ld) finished\n", requested_sym);
 285 }
 286
 287
 288 /*
 289  * Change the size of a buffer allocated with CtdlAllocUserData()
 290  */
 291 void CtdlReallocUserData(unsigned long requested_sym, size_t num_bytes)
 292 {
 293         struct CtdlSessData *ptr;
 294
 295         for (ptr = CC->FirstSessData; ptr != NULL; ptr = ptr->next)  {
 296                 if (ptr->sym_id == requested_sym) {
 297                         ptr->sym_data = reallok(ptr->sym_data, num_bytes);
 298                         return;
 299                 }
 300         }
 301
 302         lprintf(2, "CtdlReallocUserData() ERROR: symbol %ld not found!\n",
 303                 requested_sym);
 304 }
 305
 306
 307
 308
 309
 310
 311 /*
 312  * cmd_info()  -  tell the client about this server
 313  */
 314 void cmd_info(void) {
 315         cprintf("%d Server info:\n", LISTING_FOLLOWS);
 316         cprintf("%d\n", CC->cs_pid);
 317         cprintf("%s\n", config.c_nodename);
 318         cprintf("%s\n", config.c_humannode);
 319         cprintf("%s\n", config.c_fqdn);
 320         cprintf("%s\n", CITADEL);
 321         cprintf("%d\n", REV_LEVEL);
 322         cprintf("%s\n", config.c_bbs_city);
 323         cprintf("%s\n", config.c_sysadm);
 324         cprintf("%d\n", SERVER_TYPE);
 325         cprintf("%s\n", config.c_moreprompt);
 326         cprintf("1\n"); /* 1 = yes, this system supports floors */
 327         cprintf("1\n"); /* 1 = we support the extended paging options */
 328         cprintf("%s\n", CC->cs_nonce);
 329         cprintf("000\n");
 330 }
 331
 332
 333 /*
 334  * returns an asterisk if there are any express messages waiting,
 335  * space otherwise.
 336  */
 337 char CtdlCheckExpress(void) {
 338         if (CC->FirstExpressMessage == NULL) {
 339                 return(' ');
 340                 }
 341         else {
 342                 return('*');
 343                 }
 344         }
 345
 346 void cmd_time(void)
 347 {
 348    time_t tv;
 349
 350    tv = time(NULL);
 351
 352    cprintf("%d %ld\n", OK, tv);
 353 }
 354
 355 /*
 356  * Check whether two hostnames match.
 357  * "Realname" should be an actual name of a client that is trying to connect;
 358  * "testname" should be the value we are comparing it with. The idea is that we
 359  * want to compare with both the abbreviated and fully-qualified versions of
 360  * "testname;" some people define "localhost" as "localhost.foo.com," etc.
 361  */
 362 static int hostnames_match(const char *realname, const char *testname) {
 363         struct hostent *he;
 364         int retval = 0;
 365
 366         if (!strcasecmp(realname, testname))
 367                 return 1;
 368
 369 #ifdef HAVE_NONREENTRANT_NETDB
 370         begin_critical_section(S_NETDB);
 371 #endif
 372
 373         if ((he = gethostbyname(testname)) != NULL)
 374                 if (!strcasecmp(realname, he->h_name))
 375                         retval = 1;
 376
 377 #ifdef HAVE_NONREENTRANT_NETDB
 378         end_critical_section(S_NETDB);
 379 #endif
 380
 381         return retval;
 382         }
 383
 384 /*
 385  * check a hostname against the public_clients file
 386  */
 387 int is_public_client(char *where)
 388 {
 389         char buf[SIZ];
 390         FILE *fp;
 391
 392         lprintf(9, "Checking whether %s is a public client\n", where);
 393
 394         if (hostnames_match(where, "localhost")) return(1);
 395         if (hostnames_match(where, config.c_fqdn)) return(1);
 396
 397         fp = fopen("public_clients","r");
 398         if (fp == NULL) return(0);
 399
 400         while (fgets(buf, sizeof buf, fp)!=NULL) {
 401                 while (isspace((buf[strlen(buf)-1])))
 402                         buf[strlen(buf)-1] = 0;
 403                 if (hostnames_match(where,buf)) {
 404                         fclose(fp);
 405                         return(1);
 406                         }
 407                 }
 408
 409         fclose(fp);
 410         return(0);
 411         }
 412
 413
 414 /*
 415  * the client is identifying itself to the server
 416  */
 417 void cmd_iden(char *argbuf)
 418 {
 419         int dev_code;
 420         int cli_code;
 421         int rev_level;
 422         char desc[SIZ];
 423         char from_host[SIZ];
 424         struct in_addr addr;
 425         int do_lookup = 0;
 426
 427         if (num_parms(argbuf)<4) {
 428                 cprintf("%d usage error\n",ERROR);
 429                 return;
 430         }
 431
 432         dev_code = extract_int(argbuf,0);
 433         cli_code = extract_int(argbuf,1);
 434         rev_level = extract_int(argbuf,2);
 435         extract(desc,argbuf,3);
 436
 437         safestrncpy(from_host, config.c_fqdn, sizeof from_host);
 438         from_host[sizeof from_host - 1] = 0;
 439         if (num_parms(argbuf)>=5) extract(from_host,argbuf,4);
 440
 441         CC->cs_clientdev = dev_code;
 442         CC->cs_clienttyp = cli_code;
 443         CC->cs_clientver = rev_level;
 444         safestrncpy(CC->cs_clientname, desc, sizeof CC->cs_clientname);
 445         CC->cs_clientname[31] = 0;
 446
 447         if (strlen(from_host) > 0) {
 448                 if (CC->is_local_socket) do_lookup = 1;
 449                 else if (is_public_client(CC->cs_host)) do_lookup = 1;
 450         }
 451
 452         if (do_lookup) {
 453                 lprintf(9, "Looking up hostname '%s'\n", from_host);
 454                 if ((addr.s_addr = inet_addr(from_host)) != -1) {
 455                         locate_host(CC->cs_host, &addr);
 456                 }
 457                 else {
 458                         safestrncpy(CC->cs_host, from_host, sizeof CC->cs_host);
 459                         CC->cs_host[24] = 0;
 460                 }
 461         }
 462
 463         lprintf(7, "client %d/%d/%01d.%02d (%s)\n",
 464                 dev_code,
 465                 cli_code,
 466                 (rev_level / 100),
 467                 (rev_level % 100),
 468                 desc);
 469
 470         syslog(LOG_NOTICE,"session %d: client %d/%d/%01d.%02d (%s) from %s\n",
 471                 CC->cs_pid,
 472                 dev_code,
 473                 cli_code,
 474                 (rev_level / 100),
 475                 (rev_level % 100),
 476                 desc,
 477                 CC->cs_host);
 478         cprintf("%d Ok\n",OK);
 479 }
 480
 481
 482 /*
 483  * display system messages or help
 484  */
 485 void cmd_mesg(char *mname)
 486 {
 487         FILE *mfp;
 488         char targ[SIZ];
 489         char buf[SIZ];
 490         char *dirs[2];
 491
 492         extract(buf,mname,0);
 493
 494
 495         dirs[0]=mallok(64);
 496         dirs[1]=mallok(64);
 497         strcpy(dirs[0],"messages");
 498         strcpy(dirs[1],"help");
 499         mesg_locate(targ,buf,2,dirs);
 500         phree(dirs[0]);
 501         phree(dirs[1]);
 502
 503
 504         if (strlen(targ)==0) {
 505                 cprintf("%d '%s' not found.\n",ERROR,mname);
 506                 return;
 507                 }
 508
 509         mfp = fopen(targ,"r");
 510         if (mfp==NULL) {
 511                 cprintf("%d Cannot open '%s': %s\n",
 512                         ERROR,targ,strerror(errno));
 513                 return;
 514                 }
 515         cprintf("%d %s\n",LISTING_FOLLOWS,buf);
 516
 517         while (fgets(buf, (SIZ-1), mfp)!=NULL) {
 518                 buf[strlen(buf)-1] = 0;
 519                 do_help_subst(buf);
 520                 cprintf("%s\n",buf);
 521                 }
 522
 523         fclose(mfp);
 524         cprintf("000\n");
 525         }
 526
 527
 528 /*
 529  * enter system messages or help
 530  */
 531 void cmd_emsg(char *mname)
 532 {
 533         FILE *mfp;
 534         char targ[SIZ];
 535         char buf[SIZ];
 536         char *dirs[2];
 537         int a;
 538
 539         if (CtdlAccessCheck(ac_aide)) return;
 540
 541         extract(buf,mname,0);
 542         for (a=0; a<strlen(buf); ++a) {         /* security measure */
 543                 if (buf[a] == '/') buf[a] = '.';
 544                 }
 545
 546         dirs[0]=mallok(64);
 547         dirs[1]=mallok(64);
 548         strcpy(dirs[0],"messages");
 549         strcpy(dirs[1],"help");
 550         mesg_locate(targ,buf,2,dirs);
 551         phree(dirs[0]);
 552         phree(dirs[1]);
 553
 554         if (strlen(targ)==0) {
 555                 snprintf(targ, sizeof targ, "./help/%s", buf);
 556                 }
 557
 558         mfp = fopen(targ,"w");
 559         if (mfp==NULL) {
 560                 cprintf("%d Cannot open '%s': %s\n",
 561                         ERROR,targ,strerror(errno));
 562                 return;
 563                 }
 564         cprintf("%d %s\n", SEND_LISTING, targ);
 565
 566         while (client_gets(buf), strcmp(buf, "000")) {
 567                 fprintf(mfp, "%s\n", buf);
 568                 }
 569
 570         fclose(mfp);
 571         }
 572
 573
 574 /* Don't show the names of private rooms unless the viewing
 575  * user also knows the rooms.
 576  */
 577 void GenerateRoomDisplay(char *real_room,
 578                         struct CitContext *viewed,
 579                         struct CitContext *viewer) {
 580
 581         strcpy(real_room, viewed->quickroom.QRname);
 582         if (viewed->quickroom.QRflags & QR_MAILBOX) {
 583                 strcpy(real_room, &real_room[11]);
 584         }
 585         if (viewed->quickroom.QRflags & QR_PRIVATE) {
 586                 if ( (CtdlRoomAccess(&viewed->quickroom, &viewer->usersupp)
 587                    & UA_KNOWN) == 0) {
 588                         strcpy(real_room, "<private room>");
 589                 }
 590         }
 591
 592         if (viewed->cs_flags & CS_CHAT) {
 593                 while (strlen(real_room) < 14)
 594                         strcat(real_room, " ");
 595
 596                 strcpy(&real_room[14], "<chat>");
 597         }
 598
 599 }
 600
 601 /*
 602  * Convenience function.
 603  */
 604 int CtdlAccessCheck(int required_level) {
 605
 606         if (CC->internal_pgm) return(0);
 607         if (required_level >= ac_internal) {
 608                 cprintf("%d This is not a user-level command.\n",
 609                         ERROR+HIGHER_ACCESS_REQUIRED);
 610                 return(-1);
 611         }
 612
 613         if (CC->usersupp.axlevel >= 6) return(0);
 614         if (required_level >= ac_aide) {
 615                 cprintf("%d This command requires Aide access.\n",
 616                         ERROR+HIGHER_ACCESS_REQUIRED);
 617                 return(-1);
 618         }
 619
 620         if (is_room_aide()) return(0);
 621         if (required_level >= ac_room_aide) {
 622                 cprintf("%d This command requires Aide or Room Aide access.\n",
 623                         ERROR + HIGHER_ACCESS_REQUIRED);
 624                 return(-1);
 625         }
 626
 627         if (CC->logged_in) return(0);
 628         if (required_level >= ac_logged_in) {
 629                 cprintf("%d Not logged in.\n", ERROR+NOT_LOGGED_IN);
 630                 return(-1);
 631         }
 632
 633         /* shhh ... succeed quietly */
 634         return(0);
 635 }
 636
 637
 638
 639 /*
 640  * Terminate another running session
 641  */
 642 void cmd_term(char *cmdbuf)
 643 {
 644         int session_num;
 645         struct CitContext *ccptr;
 646         int found_it = 0;
 647
 648         if (CtdlAccessCheck(ac_aide)) return;
 649
 650         session_num = extract_int(cmdbuf, 0);
 651         if (session_num == CC->cs_pid) {
 652                 cprintf("%d You can't kill your own session.\n", ERROR);
 653                 return;
 654                 }
 655
 656         lprintf(9, "Locating session to kill\n");
 657         begin_critical_section(S_SESSION_TABLE);
 658         for (ccptr = ContextList; ccptr != NULL; ccptr = ccptr->next) {
 659                 if (session_num == ccptr->cs_pid) {
 660                         ccptr->kill_me = 1;
 661                         found_it = 1;
 662                         }
 663                 }
 664         end_critical_section(S_SESSION_TABLE);
 665
 666         if (found_it) {
 667                 cprintf("%d Session terminated.\n", OK);
 668                 }
 669         else {
 670                 cprintf("%d No such session.\n", ERROR);
 671                 }
 672         }
 673
 674
 675
 676
 677
 678 /*
 679  * get the paginator prompt
 680  */
 681 void cmd_more(void) {
 682         cprintf("%d %s\n",OK,config.c_moreprompt);
 683         }
 684
 685 /*
 686  * echo
 687  */
 688 void cmd_echo(char *etext)
 689 {
 690         cprintf("%d %s\n",OK,etext);
 691         }
 692
 693
 694
 695 /*
 696  * identify as internal program
 697  */
 698 void cmd_ipgm(char *argbuf)
 699 {
 700         int secret;
 701
 702         secret = extract_int(argbuf, 0);
 703         if (secret == config.c_ipgm_secret) {
 704                 CC->internal_pgm = 1;
 705                 strcpy(CC->curr_user, "<internal program>");
 706                 CC->cs_flags = CC->cs_flags|CS_STEALTH;
 707                 cprintf("%d Authenticated as an internal program.\n",OK);
 708                 }
 709         else {
 710                 cprintf("%d Authentication failed.\n",ERROR);
 711                 lprintf(3, "Warning: ipgm authentication failed.\n");
 712                 }
 713         }
 714
 715
 716 /*
 717  * Shut down the server
 718  */
 719 void cmd_down(void) {
 720
 721         if (CtdlAccessCheck(ac_aide)) return;
 722
 723         cprintf("%d Shutting down server.  Goodbye.\n", OK);
 724         time_to_die = 1;
 725         }
 726
 727 /*
 728  * Schedule or cancel a server shutdown
 729  */
 730 void cmd_scdn(char *argbuf)
 731 {
 732         int new_state;
 733
 734         if (CtdlAccessCheck(ac_aide)) return;
 735
 736         new_state = extract_int(argbuf, 0);
 737         if ((new_state == 0) || (new_state == 1)) {
 738                 ScheduledShutdown = new_state;
 739                 }
 740         cprintf("%d %d\n", OK, ScheduledShutdown);
 741 }
 742
 743
 744 /*
 745  * Set or unset asynchronous protocol mode
 746  */
 747 void cmd_asyn(char *argbuf)
 748 {
 749         int new_state;
 750
 751         new_state = extract_int(argbuf, 0);
 752         if ((new_state == 0) || (new_state == 1)) {
 753                 CC->is_async = new_state;
 754         }
 755         cprintf("%d %d\n", OK, CC->is_async);
 756 }
 757
 758
 759 /*
 760  * Generate a "nonce" for APOP-style authentication.
 761  *
 762  * RFC 1725 et al specify a PID to be placed in front of the nonce.
 763  * Quoth BTX: That would be stupid.
 764  */
 765 void generate_nonce(struct CitContext *con) {
 766         struct timeval tv;
 767
 768         memset(con->cs_nonce, NONCE_SIZE, 0);
 769         gettimeofday(&tv, NULL);
 770         memset(con->cs_nonce, NONCE_SIZE, 0);
 771         snprintf(con->cs_nonce, NONCE_SIZE, "<%d%ld@%s>",
 772                 rand(), tv.tv_usec, config.c_fqdn);
 773 }
 774
 775
 776
 777
 778 /*
 779  * Back-end function for starting a session
 780  */
 781 void begin_session(struct CitContext *con)
 782 {
 783         int len;
 784         struct sockaddr_in sin;
 785
 786         /*
 787          * Initialize some variables specific to our context.
 788          */
 789         con->logged_in = 0;
 790         con->internal_pgm = 0;
 791         con->download_fp = NULL;
 792         con->upload_fp = NULL;
 793         con->FirstExpressMessage = NULL;
 794         time(&con->lastcmd);
 795         time(&con->lastidle);
 796         strcpy(con->lastcmdname, "    ");
 797         strcpy(con->cs_clientname, "(unknown)");
 798         strcpy(con->curr_user, NLI);
 799         strcpy(con->net_node,"");
 800         strcpy(con->fake_username, "");
 801         strcpy(con->fake_postname, "");
 802         strcpy(con->fake_hostname, "");
 803         strcpy(con->fake_roomname, "");
 804         generate_nonce(con);
 805         snprintf(con->temp, sizeof con->temp, tmpnam(NULL));
 806         safestrncpy(con->cs_host, config.c_fqdn, sizeof con->cs_host);
 807         con->cs_host[sizeof con->cs_host - 1] = 0;
 808         len = sizeof sin;
 809         if (!CC->is_local_socket) {
 810                 if (!getpeername(con->client_socket,
 811                    (struct sockaddr *) &sin, &len))
 812                         locate_host(con->cs_host, &sin.sin_addr);
 813         }
 814         else {
 815                 strcpy(con->cs_host, "");
 816         }
 817         con->cs_flags = 0;
 818         con->upload_type = UPL_FILE;
 819         con->dl_is_net = 0;
 820         con->FirstSessData = NULL;
 821
 822         con->nologin = 0;
 823         if ((config.c_maxsessions > 0)&&(num_sessions > config.c_maxsessions))
 824                 con->nologin = 1;
 825
 826         lprintf(3, "citserver[%3d]: started.\n", con->cs_pid);
 827
 828         /* Run any session startup routines registered by loadable modules */
 829         PerformSessionHooks(EVT_START);
 830
 831         rec_log(CL_CONNECT, "");
 832 }
 833
 834
 835 void citproto_begin_session() {
 836         if (CC->nologin==1) {
 837                 cprintf("%d %s: Too many users are already online "
 838                         "(maximum is %d)\n",
 839                         ERROR+MAX_SESSIONS_EXCEEDED,
 840                         config.c_nodename, config.c_maxsessions);
 841                 }
 842         else {
 843                 cprintf("%d %s Citadel/UX server ready.\n",
 844                         OK, config.c_nodename);
 845                 }
 846 }
 847
 848
 849
 850
 851 /*
 852  * This loop recognizes all server commands.
 853  */
 854 void do_command_loop(void) {
 855         char cmdbuf[SIZ];
 856
 857         time(&CC->lastcmd);
 858         memset(cmdbuf, 0, sizeof cmdbuf); /* Clear it, just in case */
 859         if (client_gets(cmdbuf) < 1) {
 860                 lprintf(3, "Client socket is broken.  Ending session.\n");
 861                 CC->kill_me = 1;
 862                 return;
 863         }
 864         lprintf(5, "citserver[%3d]: %s\n", CC->cs_pid, cmdbuf);
 865
 866         /*
 867          * Let other clients see the last command we executed, and
 868          * update the idle time, but not NOOP, PEXP, or GEXP.
 869          */
 870         if ( (strncasecmp(cmdbuf, "NOOP", 4))
 871            && (strncasecmp(cmdbuf, "PEXP", 4))
 872            && (strncasecmp(cmdbuf, "GEXP", 4)) ) {
 873                 strcpy(CC->lastcmdname, "    ");
 874                 safestrncpy(CC->lastcmdname, cmdbuf,
 875                         sizeof(CC->lastcmdname) );
 876                 time(&CC->lastidle);
 877                 }
 878
 879         if ((strncasecmp(cmdbuf, "ENT0", 4))
 880            && (strncasecmp(cmdbuf, "MESG", 4))
 881            && (strncasecmp(cmdbuf, "MSGS", 4)))
 882         {
 883            CC->cs_flags &= ~CS_POSTING;
 884         }
 885
 886         if (!strncasecmp(cmdbuf,"NOOP",4)) {
 887                 cprintf("%d%cok\n",OK,CtdlCheckExpress());
 888                 }
 889
 890         else if (!strncasecmp(cmdbuf,"QUIT",4)) {
 891                 cprintf("%d Goodbye.\n",OK);
 892                 CC->kill_me = 1;
 893                 }
 894
 895         else if (!strncasecmp(cmdbuf,"ASYN",4)) {
 896                 cmd_asyn(&cmdbuf[5]);
 897                 }
 898
 899         else if (!strncasecmp(cmdbuf,"LOUT",4)) {
 900                 if (CC->logged_in) logout(CC);
 901                 cprintf("%d logged out.\n",OK);
 902                 }
 903
 904         else if (!strncasecmp(cmdbuf,"USER",4)) {
 905                 cmd_user(&cmdbuf[5]);
 906                 }
 907
 908         else if (!strncasecmp(cmdbuf,"PASS",4)) {
 909                 cmd_pass(&cmdbuf[5]);
 910                 }
 911
 912         else if (!strncasecmp(cmdbuf,"NEWU",4)) {
 913                 cmd_newu(&cmdbuf[5]);
 914                 }
 915
 916         else if (!strncasecmp(cmdbuf,"SETP",4)) {
 917                 cmd_setp(&cmdbuf[5]);
 918                 }
 919
 920         else if (!strncasecmp(cmdbuf,"LRMS",4)) {
 921                 cmd_lrms(&cmdbuf[5]);
 922                 }
 923
 924         else if (!strncasecmp(cmdbuf,"LKRA",4)) {
 925                 cmd_lkra(&cmdbuf[5]);
 926                 }
 927
 928         else if (!strncasecmp(cmdbuf,"LKRN",4)) {
 929                 cmd_lkrn(&cmdbuf[5]);
 930                 }
 931
 932         else if (!strncasecmp(cmdbuf,"LKRO",4)) {
 933                 cmd_lkro(&cmdbuf[5]);
 934                 }
 935
 936         else if (!strncasecmp(cmdbuf,"LZRM",4)) {
 937                 cmd_lzrm(&cmdbuf[5]);
 938                 }
 939
 940         else if (!strncasecmp(cmdbuf,"GETU",4)) {
 941                 cmd_getu();
 942                 }
 943
 944         else if (!strncasecmp(cmdbuf,"SETU",4)) {
 945                 cmd_setu(&cmdbuf[5]);
 946                 }
 947
 948         else if (!strncasecmp(cmdbuf,"GOTO",4)) {
 949                 cmd_goto(&cmdbuf[5]);
 950                 }
 951
 952         else if (!strncasecmp(cmdbuf,"MSGS",4)) {
 953                 cmd_msgs(&cmdbuf[5]);
 954                 }
 955
 956         else if (!strncasecmp(cmdbuf,"WHOK",4)) {
 957                 cmd_whok();
 958                 }
 959
 960         else if (!strncasecmp(cmdbuf,"RDIR",4)) {
 961                 cmd_rdir();
 962                 }
 963
 964         else if (!strncasecmp(cmdbuf,"MSG0",4)) {
 965                 cmd_msg0(&cmdbuf[5]);
 966                 }
 967
 968         else if (!strncasecmp(cmdbuf,"MSG2",4)) {
 969                 cmd_msg2(&cmdbuf[5]);
 970                 }
 971
 972         else if (!strncasecmp(cmdbuf,"MSG3",4)) {
 973                 cmd_msg3(&cmdbuf[5]);
 974                 }
 975
 976         else if (!strncasecmp(cmdbuf,"MSG4",4)) {
 977                 cmd_msg4(&cmdbuf[5]);
 978                 }
 979
 980         else if (!strncasecmp(cmdbuf,"OPNA",4)) {
 981                 cmd_opna(&cmdbuf[5]);
 982                 }
 983
 984         else if (!strncasecmp(cmdbuf,"INFO",4)) {
 985                 cmd_info();
 986                 }
 987
 988         else if (!strncasecmp(cmdbuf,"SLRP",4)) {
 989                 cmd_slrp(&cmdbuf[5]);
 990                 }
 991
 992         else if (!strncasecmp(cmdbuf,"INVT",4)) {
 993                 cmd_invt_kick(&cmdbuf[5],1);
 994                 }
 995
 996         else if (!strncasecmp(cmdbuf,"KICK",4)) {
 997                 cmd_invt_kick(&cmdbuf[5],0);
 998                 }
 999
1000         else if (!strncasecmp(cmdbuf,"GETR",4)) {
1001                 cmd_getr();
1002                 }
1003
1004         else if (!strncasecmp(cmdbuf,"SETR",4)) {
1005                 cmd_setr(&cmdbuf[5]);
1006                 }
1007
1008         else if (!strncasecmp(cmdbuf,"GETA",4)) {
1009                 cmd_geta();
1010                 }
1011
1012         else if (!strncasecmp(cmdbuf,"SETA",4)) {
1013                 cmd_seta(&cmdbuf[5]);
1014                 }
1015
1016         else if (!strncasecmp(cmdbuf,"ENT0",4)) {
1017                 cmd_ent0(&cmdbuf[5]);
1018                 }
1019
1020         else if (!strncasecmp(cmdbuf,"ENT3",4)) {
1021                 cmd_ent3(&cmdbuf[5]);
1022                 }
1023
1024         else if (!strncasecmp(cmdbuf,"RINF",4)) {
1025                 cmd_rinf();
1026                 }
1027
1028         else if (!strncasecmp(cmdbuf,"DELE",4)) {
1029                 cmd_dele(&cmdbuf[5]);
1030                 }
1031
1032         else if (!strncasecmp(cmdbuf,"KILL",4)) {
1033                 cmd_kill(&cmdbuf[5]);
1034                 }
1035
1036         else if (!strncasecmp(cmdbuf,"CRE8",4)) {
1037                 cmd_cre8(&cmdbuf[5]);
1038                 }
1039
1040         else if (!strncasecmp(cmdbuf,"MOVE",4)) {
1041                 cmd_move(&cmdbuf[5]);
1042                 }
1043
1044         else if (!strncasecmp(cmdbuf,"FORG",4)) {
1045                 cmd_forg();
1046                 }
1047
1048         else if (!strncasecmp(cmdbuf,"MESG",4)) {
1049                 cmd_mesg(&cmdbuf[5]);
1050                 }
1051
1052         else if (!strncasecmp(cmdbuf,"EMSG",4)) {
1053                 cmd_emsg(&cmdbuf[5]);
1054                 }
1055
1056         else if (!strncasecmp(cmdbuf,"GNUR",4)) {
1057                 cmd_gnur();
1058                 }
1059
1060         else if (!strncasecmp(cmdbuf,"VALI",4)) {
1061                 cmd_vali(&cmdbuf[5]);
1062                 }
1063
1064         else if (!strncasecmp(cmdbuf,"EINF",4)) {
1065                 cmd_einf(&cmdbuf[5]);
1066                 }
1067
1068         else if (!strncasecmp(cmdbuf,"LIST",4)) {
1069                 cmd_list();
1070                 }
1071
1072         else if (!strncasecmp(cmdbuf,"CHEK",4)) {
1073                 cmd_chek();
1074                 }
1075
1076         else if (!strncasecmp(cmdbuf,"DELF",4)) {
1077                 cmd_delf(&cmdbuf[5]);
1078                 }
1079
1080         else if (!strncasecmp(cmdbuf,"MOVF",4)) {
1081                 cmd_movf(&cmdbuf[5]);
1082                 }
1083
1084         else if (!strncasecmp(cmdbuf,"NETF",4)) {
1085                 cmd_netf(&cmdbuf[5]);
1086                 }
1087
1088         else if (!strncasecmp(cmdbuf,"OPEN",4)) {
1089                 cmd_open(&cmdbuf[5]);
1090                 }
1091
1092         else if (!strncasecmp(cmdbuf,"CLOS",4)) {
1093                 cmd_clos();
1094                 }
1095
1096         else if (!strncasecmp(cmdbuf,"UOPN",4)) {
1097                 cmd_uopn(&cmdbuf[5]);
1098                 }
1099
1100         else if (!strncasecmp(cmdbuf,"UCLS",4)) {
1101                 cmd_ucls(&cmdbuf[5]);
1102                 }
1103
1104         else if (!strncasecmp(cmdbuf,"READ",4)) {
1105                 cmd_read(&cmdbuf[5]);
1106                 }
1107
1108         else if (!strncasecmp(cmdbuf,"WRIT",4)) {
1109                 cmd_writ(&cmdbuf[5]);
1110                 }
1111
1112         else if (!strncasecmp(cmdbuf,"QUSR",4)) {
1113                 cmd_qusr(&cmdbuf[5]);
1114                 }
1115
1116         else if (!strncasecmp(cmdbuf,"ECHO",4)) {
1117                 cmd_echo(&cmdbuf[5]);
1118                 }
1119
1120         else if (!strncasecmp(cmdbuf,"OIMG",4)) {
1121                 cmd_oimg(&cmdbuf[5]);
1122                 }
1123
1124         else if (!strncasecmp(cmdbuf,"MORE",4)) {
1125                 cmd_more();
1126                 }
1127
1128         else if (!strncasecmp(cmdbuf,"NDOP",4)) {
1129                 cmd_ndop(&cmdbuf[5]);
1130                 }
1131
1132         else if (!strncasecmp(cmdbuf,"NUOP",4)) {
1133                 cmd_nuop(&cmdbuf[5]);
1134                 }
1135
1136         else if (!strncasecmp(cmdbuf,"LFLR",4)) {
1137                 cmd_lflr();
1138                 }
1139
1140         else if (!strncasecmp(cmdbuf,"CFLR",4)) {
1141                 cmd_cflr(&cmdbuf[5]);
1142                 }
1143
1144         else if (!strncasecmp(cmdbuf,"KFLR",4)) {
1145                 cmd_kflr(&cmdbuf[5]);
1146                 }
1147
1148         else if (!strncasecmp(cmdbuf,"EFLR",4)) {
1149                 cmd_eflr(&cmdbuf[5]);
1150                 }
1151
1152         else if (!strncasecmp(cmdbuf,"IDEN",4)) {
1153                 cmd_iden(&cmdbuf[5]);
1154                 }
1155
1156         else if (!strncasecmp(cmdbuf,"IPGM",4)) {
1157                 cmd_ipgm(&cmdbuf[5]);
1158                 }
1159
1160         else if (!strncasecmp(cmdbuf,"TERM",4)) {
1161                 cmd_term(&cmdbuf[5]);
1162                 }
1163
1164         else if (!strncasecmp(cmdbuf,"DOWN",4)) {
1165                 cmd_down();
1166                 }
1167
1168         else if (!strncasecmp(cmdbuf,"SCDN",4)) {
1169                 cmd_scdn(&cmdbuf[5]);
1170                 }
1171
1172         else if (!strncasecmp(cmdbuf, "NSET", 4)) {
1173                 cmd_nset(&cmdbuf[5]);
1174                 }
1175
1176         else if (!strncasecmp(cmdbuf, "UIMG", 4)) {
1177                 cmd_uimg(&cmdbuf[5]);
1178                 }
1179
1180         else if (!strncasecmp(cmdbuf, "TIME", 4)) {
1181                 cmd_time();
1182                 }
1183
1184         else if (!strncasecmp(cmdbuf, "AGUP", 4)) {
1185                 cmd_agup(&cmdbuf[5]);
1186                 }
1187
1188         else if (!strncasecmp(cmdbuf, "ASUP", 4)) {
1189                 cmd_asup(&cmdbuf[5]);
1190                 }
1191
1192         else if (!strncasecmp(cmdbuf, "GPEX", 4)) {
1193                 cmd_gpex(&cmdbuf[5]);
1194                 }
1195
1196         else if (!strncasecmp(cmdbuf, "SPEX", 4)) {
1197                 cmd_spex(&cmdbuf[5]);
1198                 }
1199
1200         else if (!strncasecmp(cmdbuf, "CONF", 4)) {
1201                 cmd_conf(&cmdbuf[5]);
1202                 }
1203
1204         else if (!strncasecmp(cmdbuf, "SEEN", 4)) {
1205                 cmd_seen(&cmdbuf[5]);
1206                 }
1207
1208 #ifdef DEBUG_MEMORY_LEAKS
1209         else if (!strncasecmp(cmdbuf, "LEAK", 4)) {
1210                 dump_tracked();
1211                 }
1212 #endif
1213
1214         else if (!DLoader_Exec_Cmd(cmdbuf))
1215                 {
1216                    cprintf("%d Unrecognized or unsupported command.\n",
1217                             ERROR);
1218                 }
1219
1220         /* Run any after-each-command outines registered by modules */
1221         PerformSessionHooks(EVT_CMD);
1222 }