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