citadel/citserver.c

   1 /* $Id$ */
   2 #include "sysdep.h"
   3 #include <stdlib.h>
   4 #include <unistd.h>
   5 #include <stdio.h>
   6 #include <fcntl.h>
   7 #include <signal.h>
   8 #include <time.h>
   9 #include <ctype.h>
  10 #include <string.h>
  11 #include <errno.h>
  12 #include <limits.h>
  13 #include <syslog.h>
  14 #include <dlfcn.h>
  15 #include <netdb.h>
  16 #include <sys/types.h>
  17 #include <sys/socket.h>
  18 #include <netinet/in.h>
  19 #include <arpa/inet.h>
  20 #include "citadel.h"
  21 #include "server.h"
  22 #include "sysdep_decls.h"
  23 #include "citserver.h"
  24 #include "config.h"
  25 #include "database.h"
  26 #include "housekeeping.h"
  27 #include "user_ops.h"
  28 #include "logging.h"
  29 #include "msgbase.h"
  30 #include "support.h"
  31 #include "locate_host.h"
  32 #include "room_ops.h"
  33 #include "file_ops.h"
  34 #include "dynloader.h"
  35 #include "policy.h"
  36 #include "control.h"
  37 #include "tools.h"
  38
  39 struct CitContext *ContextList = NULL;
  40 char *unique_session_numbers;
  41 int ScheduledShutdown = 0;
  42 int do_defrag = 0;
  43
  44 /*
  45  * Various things that need to be initialized at startup
  46  */
  47 void master_startup(void) {
  48         lprintf(7, "Opening databases\n");
  49         open_databases();
  50
  51         if (do_defrag)
  52                 defrag_databases();
  53
  54         lprintf(7, "Checking floor reference counts\n");
  55         check_ref_counts();
  56
  57         lprintf(7, "Creating base rooms (if necessary)\n");
  58         create_room(BASEROOM, 0, "", 0);
  59         create_room(AIDEROOM, 4, "", 0);
  60         create_room(config.c_twitroom, 0, "", 0);
  61         }
  62
  63 /*
  64  * Cleanup routine to be called when the server is shutting down.
  65  */
  66 void master_cleanup(void) {
  67         struct CleanupFunctionHook *fcn;
  68
  69         /* Cancel all running sessions */
  70         lprintf(7, "Cancelling running sessions...\n");
  71
  72 /* FIX do something here
  73         while (ContextList != NULL) {
  74                 }
  75  */
  76
  77         /* Run any cleanup routines registered by loadable modules */
  78         for (fcn = CleanupHookTable; fcn != NULL; fcn = fcn->next) {
  79                 (*fcn->h_function_pointer)();
  80                 }
  81
  82         /* Close databases */
  83         lprintf(7, "Closing databases\n");
  84         close_databases();
  85
  86         /* Do system-dependent stuff */
  87         sysdep_master_cleanup();
  88
  89         /* Now go away. */
  90         lprintf(3, "citserver: exiting.\n");
  91         fflush(stdout); fflush(stderr);
  92         exit(0);
  93         }
  94
  95
  96 /*
  97  * Free any per-session data allocated by modules or whatever
  98  */
  99 void deallocate_user_data(struct CitContext *con)
 100 {
 101         struct CtdlSessData *ptr;
 102
 103         begin_critical_section(S_SESSION_TABLE);
 104         while (con->FirstSessData != NULL) {
 105                 lprintf(9, "Deallocating user data symbol %ld\n",
 106                         con->FirstSessData->sym_id);
 107                 if (con->FirstSessData->sym_data != NULL)
 108                         phree(con->FirstSessData->sym_data);
 109                 ptr = con->FirstSessData->next;
 110                 phree(con->FirstSessData);
 111                 con->FirstSessData = ptr;
 112         }
 113         end_critical_section(S_SESSION_TABLE);
 114 }
 115
 116
 117
 118
 119 /*
 120  * Terminate a session and remove its context data structure.
 121  */
 122 void RemoveContext (struct CitContext *con)
 123 {
 124         struct CitContext *ptr = NULL;
 125         struct CitContext *ToFree = NULL;
 126
 127         lprintf(9, "RemoveContext() called\n");
 128         if (con==NULL) {
 129                 lprintf(5, "WARNING: RemoveContext() called with NULL!\n");
 130                 return;
 131                 }
 132
 133         /* Remove the context from the global context list.  This needs
 134          * to get done FIRST to avoid concurrency problems.  It is *vitally*
 135          * important to keep num_sessions accurate!!
 136          */
 137         lprintf(7, "Removing context for session %d\n", con->cs_pid);
 138         begin_critical_section(S_SESSION_TABLE);
 139         if (ContextList == con) {
 140                 ToFree = ContextList;
 141                 ContextList = ContextList->next;
 142                 --num_sessions;
 143                 }
 144         else {
 145                 for (ptr = ContextList; ptr != NULL; ptr = ptr->next) {
 146                         if (ptr->next == con) {
 147                                 ToFree = ptr->next;
 148                                 ptr->next = ptr->next->next;
 149                                 --num_sessions;
 150                                 }
 151                         }
 152                 }
 153         end_critical_section(S_SESSION_TABLE);
 154
 155         if (ToFree == NULL) {
 156                 lprintf(9, "RemoveContext() found nothing to remove\n");
 157                 return;
 158         }
 159
 160         /* Now handle all of the administrivia. */
 161         lprintf(7, "Calling logout(%d)\n", con->cs_pid);
 162         logout(con);
 163
 164         rec_log(CL_TERMINATE, con->curr_user);
 165         unlink(con->temp);
 166         lprintf(3, "citserver[%3d]: ended.\n", con->cs_pid);
 167
 168         /* Run any cleanup routines registered by loadable modules */
 169         PerformSessionHooks(EVT_STOP);
 170
 171         syslog(LOG_NOTICE,"session %d ended", con->cs_pid);
 172
 173         /* Deallocate any user-data attached to this session */
 174         deallocate_user_data(con);
 175
 176         /* If the client is still connected, blow 'em away. */
 177         lprintf(7, "Closing socket %d\n", con->client_socket);
 178         close(con->client_socket);
 179
 180         /* Tell the housekeeping thread to check to see if this is the time
 181          * to initiate a scheduled shutdown event.
 182          */
 183         enter_housekeeping_cmd("SCHED_SHUTDOWN");
 184
 185         /* Free up the memory used by this context */
 186         phree(con);
 187
 188         lprintf(7, "Done with RemoveContext()\n");
 189 }
 190
 191
 192
 193 /*
 194  * Get a dynamic symbol number for per-session user data.
 195  * This API call should be made only ONCE per symbol per citserver run.
 196  */
 197 int CtdlGetDynamicSymbol()
 198 {
 199         static unsigned int next_symbol = SYM_MAX;
 200         return ++next_symbol;
 201 }
 202
 203
 204
 205 /*
 206  * Return a pointer to some generic per-session user data.
 207  * (This function returns NULL if the requested symbol is not allocated.)
 208  *
 209  * NOTE: we use critical sections for allocating and de-allocating these,
 210  *       but not for locating one.
 211  */
 212 void *CtdlGetUserData(unsigned long requested_sym)
 213 {
 214         struct CtdlSessData *ptr;
 215
 216         for (ptr = CC->FirstSessData; ptr != NULL; ptr = ptr->next)
 217                 if (ptr->sym_id == requested_sym)
 218                         return(ptr->sym_data);
 219
 220         lprintf(2, "ERROR! CtdlGetUserData(%ld) symbol not allocated\n",
 221                 requested_sym);
 222         return NULL;
 223 }
 224
 225
 226 /*
 227  * Allocate some generic per-session user data.
 228  */
 229 void CtdlAllocUserData(unsigned long requested_sym, size_t num_bytes)
 230 {
 231         struct CtdlSessData *ptr;
 232
 233         lprintf(9, "CtdlAllocUserData(%ld) called\n", requested_sym);
 234
 235         /* Fail silently if the symbol is already registered. */
 236         for (ptr = CC->FirstSessData; ptr != NULL; ptr = ptr->next)  {
 237                 if (ptr->sym_id == requested_sym) {
 238                         return;
 239                 }
 240         }
 241
 242         /* Grab us some memory!  Dem's good eatin' !!  */
 243         ptr = mallok(sizeof(struct CtdlSessData));
 244         ptr->sym_id = requested_sym;
 245         ptr->sym_data = mallok(num_bytes);
 246         memset(ptr->sym_data, 0, num_bytes);
 247
 248         begin_critical_section(S_SESSION_TABLE);
 249         ptr->next = CC->FirstSessData;
 250         CC->FirstSessData = ptr;
 251         end_critical_section(S_SESSION_TABLE);
 252
 253         lprintf(9, "CtdlAllocUserData(%ld) finished\n", requested_sym);
 254 }
 255
 256
 257
 258
 259
 260
 261 /*
 262  * cmd_info()  -  tell the client about this server
 263  */
 264 void cmd_info(void) {
 265         cprintf("%d Server info:\n",LISTING_FOLLOWS);
 266         cprintf("%d\n",CC->cs_pid);
 267         cprintf("%s\n",config.c_nodename);
 268         cprintf("%s\n",config.c_humannode);
 269         cprintf("%s\n",config.c_fqdn);
 270         cprintf("%s\n",CITADEL);
 271         cprintf("%d\n",REV_LEVEL);
 272         cprintf("%s\n",config.c_bbs_city);
 273         cprintf("%s\n",config.c_sysadm);
 274         cprintf("%d\n",SERVER_TYPE);
 275         cprintf("%s\n",config.c_moreprompt);
 276         cprintf("1\n"); /* 1 = yes, this system supports floors */
 277         cprintf("1\n"); /* 1 = we support the extended paging options */
 278         cprintf("000\n");
 279         }
 280
 281 void cmd_rchg(char *argbuf)
 282 {
 283         char newroomname[256];
 284
 285         extract(newroomname, argbuf, 0);
 286         newroomname[ROOMNAMELEN-1] = 0;
 287         if (strlen(newroomname) > 0) {
 288                 safestrncpy(CC->fake_roomname, newroomname,
 289                         sizeof(CC->fake_roomname) );
 290                 }
 291         else {
 292                 strcpy(CC->fake_roomname, "");
 293                 }
 294         cprintf("%d OK\n", OK);
 295 }
 296
 297 void cmd_hchg(char *argbuf)
 298 {
 299         char newhostname[256];
 300
 301         extract(newhostname, argbuf, 0);
 302         if (strlen(newhostname) > 0) {
 303                 safestrncpy(CC->fake_hostname, newhostname,
 304                         sizeof(CC->fake_hostname) );
 305                 }
 306         else {
 307                 strcpy(CC->fake_hostname, "");
 308                 }
 309         cprintf("%d OK\n", OK);
 310 }
 311
 312 void cmd_uchg(char *argbuf)
 313 {
 314
 315         char newusername[256];
 316
 317         extract(newusername, argbuf, 0);
 318
 319         if (CC->usersupp.axlevel < 6) {
 320                 cprintf("%d You must be an Aide to masquerade your name.\n",
 321                         ERROR+HIGHER_ACCESS_REQUIRED);
 322                 return;
 323         }
 324
 325         if (strlen(newusername) > 0) {
 326                 CC->cs_flags &= ~CS_STEALTH;
 327                 memset(CC->fake_username, 0, 32);
 328                 if (strncasecmp(newusername, CC->curr_user,
 329                                 strlen(CC->curr_user)))
 330                         safestrncpy(CC->fake_username, newusername,
 331                                 sizeof(CC->fake_username));
 332         }
 333         else {
 334                 CC->fake_username[0] = '\0';
 335                 CC->cs_flags |= CS_STEALTH;
 336         }
 337         cprintf("%d\n",OK);
 338 }
 339
 340
 341
 342 /*
 343  * returns an asterisk if there are any express messages waiting,
 344  * space otherwise.
 345  */
 346 char check_express(void) {
 347         if (CC->FirstExpressMessage == NULL) {
 348                 return(' ');
 349                 }
 350         else {
 351                 return('*');
 352                 }
 353         }
 354
 355 void cmd_time(void)
 356 {
 357    time_t tv;
 358
 359    tv = time(NULL);
 360
 361    cprintf("%d %ld\n", OK, tv);
 362 }
 363
 364 /*
 365  * Check whether two hostnames match.
 366  * "Realname" should be an actual name of a client that is trying to connect;
 367  * "testname" should be the value we are comparing it with. The idea is that we
 368  * want to compare with both the abbreviated and fully-qualified versions of
 369  * "testname;" some people define "localhost" as "localhost.foo.com," etc.
 370  */
 371 static int hostnames_match(const char *realname, const char *testname) {
 372         struct hostent *he;
 373         int retval = 0;
 374
 375         if (!strcasecmp(realname, testname))
 376                 return 1;
 377
 378 #ifdef HAVE_NONREENTRANT_NETDB
 379         begin_critical_section(S_NETDB);
 380 #endif
 381
 382         if ((he = gethostbyname(testname)) != NULL)
 383                 if (!strcasecmp(realname, he->h_name))
 384                         retval = 1;
 385
 386 #ifdef HAVE_NONREENTRANT_NETDB
 387         end_critical_section(S_NETDB);
 388 #endif
 389
 390         return retval;
 391         }
 392
 393 /*
 394  * check a hostname against the public_clients file
 395  */
 396 int is_public_client(char *where)
 397 {
 398         char buf[256];
 399         FILE *fp;
 400
 401         if (hostnames_match(where,"localhost")) return(1);
 402         if (hostnames_match(where,config.c_fqdn)) return(1);
 403
 404         fp = fopen("public_clients","r");
 405         if (fp == NULL) return(0);
 406
 407         while (fgets(buf,256,fp)!=NULL) {
 408                 while (isspace((buf[strlen(buf)-1])))
 409                         buf[strlen(buf)-1] = 0;
 410                 if (hostnames_match(where,buf)) {
 411                         fclose(fp);
 412                         return(1);
 413                         }
 414                 }
 415
 416         fclose(fp);
 417         return(0);
 418         }
 419
 420
 421 /*
 422  * the client is identifying itself to the server
 423  */
 424 void cmd_iden(char *argbuf)
 425 {
 426         int dev_code;
 427         int cli_code;
 428         int rev_level;
 429         char desc[256];
 430         char from_host[256];
 431         struct in_addr addr;
 432
 433         if (num_parms(argbuf)<4) {
 434                 cprintf("%d usage error\n",ERROR);
 435                 return;
 436                 }
 437
 438         dev_code = extract_int(argbuf,0);
 439         cli_code = extract_int(argbuf,1);
 440         rev_level = extract_int(argbuf,2);
 441         extract(desc,argbuf,3);
 442
 443         safestrncpy(from_host, config.c_fqdn, sizeof from_host);
 444         from_host[sizeof from_host - 1] = 0;
 445         if (num_parms(argbuf)>=5) extract(from_host,argbuf,4);
 446
 447         CC->cs_clientdev = dev_code;
 448         CC->cs_clienttyp = cli_code;
 449         CC->cs_clientver = rev_level;
 450         safestrncpy(CC->cs_clientname, desc, sizeof CC->cs_clientname);
 451         CC->cs_clientname[31] = 0;
 452
 453         lprintf(9, "Looking up hostname '%s'\n", from_host);
 454         if ((strlen(from_host)>0) &&
 455            (is_public_client(CC->cs_host))) {
 456                 if ((addr.s_addr = inet_addr(from_host)) != INADDR_NONE)
 457                         locate_host(CC->cs_host, &addr);
 458                 else {
 459                         safestrncpy(CC->cs_host, from_host, sizeof CC->cs_host);
 460                         CC->cs_host[24] = 0;
 461                         }
 462                 }
 463
 464         syslog(LOG_NOTICE,"client %d/%d/%01d.%02d (%s)\n",
 465                 dev_code,
 466                 cli_code,
 467                 (rev_level / 100),
 468                 (rev_level % 100),
 469                 desc);
 470                 cprintf("%d Ok\n",OK);
 471         }
 472
 473
 474 /*
 475  * enter or exit "stealth mode"
 476  */
 477 void cmd_stel(char *cmdbuf)
 478 {
 479         int requested_mode;
 480
 481         requested_mode = extract_int(cmdbuf,0);
 482         if (requested_mode !=0) requested_mode = 1;
 483
 484         if (!CC->logged_in) {
 485                 cprintf("%d Not logged in.\n",ERROR+NOT_LOGGED_IN);
 486                 return;
 487                 }
 488
 489         if (CC->usersupp.axlevel < 6) {
 490                 cprintf("%d You must be an Aide to use stealth mode.\n",
 491                         ERROR+HIGHER_ACCESS_REQUIRED);
 492                 return;
 493                 }
 494
 495         if (CC->cs_flags & CS_STEALTH) {
 496                 if (requested_mode == 0)
 497                         CC->cs_flags = CC->cs_flags-CS_STEALTH;
 498                 }
 499         else {
 500                 if (requested_mode == 1)
 501                         CC->cs_flags = CC->cs_flags|CS_STEALTH;
 502                 }
 503
 504         cprintf("%d Ok\n",OK);
 505         }
 506
 507
 508
 509
 510 /*
 511  * display system messages or help
 512  */
 513 void cmd_mesg(char *mname)
 514 {
 515         FILE *mfp;
 516         char targ[256];
 517         char buf[256];
 518         char *dirs[2];
 519
 520         extract(buf,mname,0);
 521
 522
 523         dirs[0]=mallok(64);
 524         dirs[1]=mallok(64);
 525         strcpy(dirs[0],"messages");
 526         strcpy(dirs[1],"help");
 527         mesg_locate(targ,buf,2,dirs);
 528         phree(dirs[0]);
 529         phree(dirs[1]);
 530
 531
 532         if (strlen(targ)==0) {
 533                 cprintf("%d '%s' not found.\n",ERROR,mname);
 534                 return;
 535                 }
 536
 537         mfp = fopen(targ,"r");
 538         if (mfp==NULL) {
 539                 cprintf("%d Cannot open '%s': %s\n",
 540                         ERROR,targ,strerror(errno));
 541                 return;
 542                 }
 543         cprintf("%d %s\n",LISTING_FOLLOWS,buf);
 544
 545         while (fgets(buf,255,mfp)!=NULL) {
 546                 buf[strlen(buf)-1] = 0;
 547                 do_help_subst(buf);
 548                 cprintf("%s\n",buf);
 549                 }
 550
 551         fclose(mfp);
 552         cprintf("000\n");
 553         }
 554
 555
 556 /*
 557  * enter system messages or help
 558  */
 559 void cmd_emsg(char *mname)
 560 {
 561         FILE *mfp;
 562         char targ[256];
 563         char buf[256];
 564         char *dirs[2];
 565         int a;
 566
 567         if (CC->usersupp.axlevel < 6) {
 568                 cprintf("%d You must be an Aide to edit system messages.\n",
 569                         ERROR+HIGHER_ACCESS_REQUIRED);
 570                 return;
 571                 }
 572
 573         extract(buf,mname,0);
 574         for (a=0; a<strlen(buf); ++a) {         /* security measure */
 575                 if (buf[a] == '/') buf[a] = '.';
 576                 }
 577
 578         dirs[0]=mallok(64);
 579         dirs[1]=mallok(64);
 580         strcpy(dirs[0],"messages");
 581         strcpy(dirs[1],"help");
 582         mesg_locate(targ,buf,2,dirs);
 583         phree(dirs[0]);
 584         phree(dirs[1]);
 585
 586         if (strlen(targ)==0) {
 587                 snprintf(targ, sizeof targ, "./help/%s", buf);
 588                 }
 589
 590         mfp = fopen(targ,"w");
 591         if (mfp==NULL) {
 592                 cprintf("%d Cannot open '%s': %s\n",
 593                         ERROR,targ,strerror(errno));
 594                 return;
 595                 }
 596         cprintf("%d %s\n", SEND_LISTING, targ);
 597
 598         while (client_gets(buf), strcmp(buf, "000")) {
 599                 fprintf(mfp, "%s\n", buf);
 600                 }
 601
 602         fclose(mfp);
 603         }
 604
 605
 606 /* Don't show the names of private rooms unless the viewing
 607  * user also knows the rooms.
 608  */
 609 void GenerateRoomDisplay(char *real_room,
 610                         struct CitContext *viewed,
 611                         struct CitContext *viewer) {
 612
 613         strcpy(real_room, viewed->quickroom.QRname);
 614         if (viewed->quickroom.QRflags & QR_MAILBOX) {
 615                 strcpy(real_room, &real_room[11]);
 616         }
 617         if (viewed->quickroom.QRflags & QR_PRIVATE) {
 618                 if ( (CtdlRoomAccess(&viewed->quickroom, &viewer->usersupp)
 619                    & UA_KNOWN) == 0) {
 620                         strcpy(real_room, "<private room>");
 621                 }
 622         }
 623
 624         if (viewed->cs_flags & CS_CHAT) {
 625                 while (strlen(real_room) < 14)
 626                         strcat(real_room, " ");
 627
 628                 strcpy(&real_room[14], "<chat>");
 629         }
 630
 631 }
 632
 633
 634 /*
 635  * who's online
 636  */
 637 void cmd_rwho(void) {
 638         struct CitContext *cptr;
 639         int spoofed = 0;
 640         int aide;
 641         char un[40];
 642         char real_room[ROOMNAMELEN], room[ROOMNAMELEN];
 643         char host[40], flags[5];
 644
 645         aide = CC->usersupp.axlevel >= 6;
 646         cprintf("%d%c \n", LISTING_FOLLOWS, check_express() );
 647
 648         for (cptr = ContextList; cptr != NULL; cptr = cptr->next)
 649         {
 650                 flags[0] = '\0';
 651                 spoofed = 0;
 652
 653                 if (cptr->cs_flags & CS_POSTING)
 654                    strcat(flags, "*");
 655                 else
 656                    strcat(flags, ".");
 657
 658                 if (cptr->fake_username[0])
 659                 {
 660                    strcpy(un, cptr->fake_username);
 661                    spoofed = 1;
 662                 }
 663                 else
 664                    strcpy(un, cptr->curr_user);
 665
 666                 if (cptr->fake_hostname[0])
 667                 {
 668                    strcpy(host, cptr->fake_hostname);
 669                    spoofed = 1;
 670                 }
 671                 else
 672                    strcpy(host, cptr->cs_host);
 673
 674                 GenerateRoomDisplay(real_room, cptr, CC);
 675
 676                 if (cptr->fake_roomname[0]) {
 677                         strcpy(room, cptr->fake_roomname);
 678                         spoofed = 1;
 679                 }
 680                 else {
 681                         strcpy(room, real_room);
 682                 }
 683
 684                 if ((aide) && (spoofed))
 685                    strcat(flags, "+");
 686
 687                 if ((cptr->cs_flags & CS_STEALTH) && (aide))
 688                    strcat(flags, "-");
 689
 690                 if (((cptr->cs_flags&CS_STEALTH)==0) || (aide))
 691                 {
 692                         cprintf("%d|%s|%s|%s|%s|%ld|%s|%s\n",
 693                                 cptr->cs_pid, un, room,
 694                                 host, cptr->cs_clientname,
 695                                 (long)(cptr->lastidle),
 696                                 cptr->lastcmdname, flags);
 697                 }
 698                 if ((spoofed) && (aide))
 699                 {
 700                         cprintf("%d|%s|%s|%s|%s|%ld|%s|%s\n",
 701                                 cptr->cs_pid, cptr->curr_user,
 702                                 real_room,
 703                                 cptr->cs_host, cptr->cs_clientname,
 704                                 (long)(cptr->lastidle),
 705                                 cptr->lastcmdname, flags);
 706
 707                 }
 708         }
 709
 710         /* Now it's magic time.  Before we finish, call any EVT_RWHO hooks
 711          * so that external paging modules such as serv_icq can add more
 712          * content to the Wholist.
 713          */
 714         PerformSessionHooks(EVT_RWHO);
 715         cprintf("000\n");
 716         }
 717
 718
 719 /*
 720  * Terminate another running session
 721  */
 722 void cmd_term(char *cmdbuf)
 723 {
 724         int session_num;
 725         struct CitContext *ccptr;
 726         int found_it = 0;
 727
 728         if (!CC->logged_in) {
 729                 cprintf("%d Not logged in.\n",ERROR+NOT_LOGGED_IN);
 730                 return;
 731                 }
 732
 733         if (CC->usersupp.axlevel < 6) {
 734                 cprintf("%d You must be an Aide to terminate sessions.\n",
 735                         ERROR+HIGHER_ACCESS_REQUIRED);
 736                 return;
 737                 }
 738
 739         session_num = extract_int(cmdbuf, 0);
 740         if (session_num == CC->cs_pid) {
 741                 cprintf("%d You can't kill your own session.\n", ERROR);
 742                 return;
 743                 }
 744
 745         lprintf(9, "Locating session to kill\n");
 746         begin_critical_section(S_SESSION_TABLE);
 747         for (ccptr = ContextList; ccptr != NULL; ccptr = ccptr->next) {
 748                 if (session_num == ccptr->cs_pid) {
 749                         ccptr->kill_me = 1;
 750                         found_it = 1;
 751                         }
 752                 }
 753         end_critical_section(S_SESSION_TABLE);
 754
 755         if (found_it) {
 756                 cprintf("%d Session terminated.\n", OK);
 757                 }
 758         else {
 759                 cprintf("%d No such session.\n", ERROR);
 760                 }
 761         }
 762
 763
 764
 765
 766
 767 /*
 768  * get the paginator prompt
 769  */
 770 void cmd_more(void) {
 771         cprintf("%d %s\n",OK,config.c_moreprompt);
 772         }
 773
 774 /*
 775  * echo
 776  */
 777 void cmd_echo(char *etext)
 778 {
 779         cprintf("%d %s\n",OK,etext);
 780         }
 781
 782
 783
 784 /*
 785  * identify as internal program
 786  */
 787 void cmd_ipgm(char *argbuf)
 788 {
 789         int secret;
 790
 791         secret = extract_int(argbuf, 0);
 792         if (secret == config.c_ipgm_secret) {
 793                 CC->internal_pgm = 1;
 794                 strcpy(CC->curr_user, "<internal program>");
 795                 CC->cs_flags = CC->cs_flags|CS_STEALTH;
 796                 cprintf("%d Authenticated as an internal program.\n",OK);
 797                 }
 798         else {
 799                 cprintf("%d Authentication failed.\n",ERROR);
 800                 lprintf(3, "Warning: ipgm authentication failed.\n");
 801                 }
 802         }
 803
 804
 805 /*
 806  * Shut down the server
 807  */
 808 void cmd_down(void) {
 809         if (!CC->logged_in) {
 810                 cprintf("%d Not logged in.\n", ERROR+NOT_LOGGED_IN);
 811                 return;
 812                 }
 813
 814         if (CC->usersupp.axlevel < 6) {
 815                 cprintf("%d You must be an Aide to shut down the server.\n",
 816                         ERROR+HIGHER_ACCESS_REQUIRED);
 817                 return;
 818                 }
 819
 820         cprintf("%d Shutting down server.  Goodbye.\n", OK);
 821         master_cleanup();
 822         }
 823
 824 /*
 825  * Schedule or cancel a server shutdown
 826  */
 827 void cmd_scdn(char *argbuf)
 828 {
 829         int new_state;
 830
 831         if (!CC->logged_in) {
 832                 cprintf("%d Not logged in.\n",ERROR+NOT_LOGGED_IN);
 833                 return;
 834                 }
 835
 836         if (CC->usersupp.axlevel < 6) {
 837                 cprintf("%d You must be an Aide to schedule a shutdown.\n",
 838                         ERROR+HIGHER_ACCESS_REQUIRED);
 839                 return;
 840                 }
 841
 842         new_state = extract_int(argbuf, 0);
 843         if ((new_state == 0) || (new_state == 1)) {
 844                 ScheduledShutdown = new_state;
 845                 }
 846         cprintf("%d %d\n", OK, ScheduledShutdown);
 847         }
 848
 849
 850 /*
 851  * Back-end function for starting a session
 852  */
 853 void begin_session(struct CitContext *con)
 854 {
 855         int len;
 856         struct sockaddr_in sin;
 857
 858         /*
 859          * Initialize some variables specific to our context.
 860          */
 861         con->logged_in = 0;
 862         con->internal_pgm = 0;
 863         con->download_fp = NULL;
 864         con->upload_fp = NULL;
 865         con->FirstExpressMessage = NULL;
 866         time(&con->lastcmd);
 867         time(&con->lastidle);
 868         strcpy(con->lastcmdname, "    ");
 869         strcpy(con->cs_clientname, "(unknown)");
 870         strcpy(con->curr_user, NLI);
 871         strcpy(con->net_node,"");
 872         snprintf(con->temp, sizeof con->temp, tmpnam(NULL));
 873         safestrncpy(con->cs_host, config.c_fqdn, sizeof con->cs_host);
 874         con->cs_host[sizeof con->cs_host - 1] = 0;
 875         len = sizeof sin;
 876         if (!getpeername(con->client_socket, (struct sockaddr *) &sin, &len))
 877                 locate_host(con->cs_host, &sin.sin_addr);
 878         con->cs_flags = 0;
 879         con->upload_type = UPL_FILE;
 880         con->dl_is_net = 0;
 881         con->FirstSessData = NULL;
 882
 883         con->nologin = 0;
 884         if ((config.c_maxsessions > 0)&&(num_sessions > config.c_maxsessions))
 885                 con->nologin = 1;
 886
 887         lprintf(3, "citserver[%3d]: started.\n", con->cs_pid);
 888
 889         /* Run any session startup routines registered by loadable modules */
 890         PerformSessionHooks(EVT_START);
 891
 892         rec_log(CL_CONNECT, "");
 893 }
 894
 895
 896 void citproto_begin_session() {
 897         if (CC->nologin==1) {
 898                 cprintf("%d %s: Too many users are already online "
 899                         "(maximum is %d)\n",
 900                         ERROR+MAX_SESSIONS_EXCEEDED,
 901                         config.c_nodename, config.c_maxsessions);
 902                 }
 903         else {
 904                 cprintf("%d %s Citadel/UX server ready.\n",
 905                         OK, config.c_nodename);
 906                 }
 907 }
 908
 909
 910
 911
 912 /*
 913  * This loop recognizes all server commands.
 914  */
 915 void do_command_loop(void) {
 916         char cmdbuf[256];
 917
 918         time(&CC->lastcmd);
 919         memset(cmdbuf, 0, sizeof cmdbuf); /* Clear it, just in case */
 920         if (client_gets(cmdbuf) < 1) {
 921                 lprintf(3, "Client socket is broken.  Ending session.\n");
 922                 CC->kill_me = 1;
 923                 return;
 924         }
 925         lprintf(5, "citserver[%3d]: %s\n", CC->cs_pid, cmdbuf);
 926
 927         /*
 928          * Let other clients see the last command we executed, and
 929          * update the idle time, but not NOOP, PEXP, or GEXP.
 930          */
 931         if ( (strncasecmp(cmdbuf, "NOOP", 4))
 932            && (strncasecmp(cmdbuf, "PEXP", 4))
 933            && (strncasecmp(cmdbuf, "GEXP", 4)) ) {
 934                 strcpy(CC->lastcmdname, "    ");
 935                 safestrncpy(CC->lastcmdname, cmdbuf,
 936                         sizeof(CC->lastcmdname) );
 937                 time(&CC->lastidle);
 938                 }
 939
 940         if ((strncasecmp(cmdbuf, "ENT0", 4))
 941            && (strncasecmp(cmdbuf, "MESG", 4))
 942            && (strncasecmp(cmdbuf, "MSGS", 4)))
 943         {
 944            CC->cs_flags &= ~CS_POSTING;
 945         }
 946
 947         if (!strncasecmp(cmdbuf,"NOOP",4)) {
 948                 cprintf("%d%cok\n",OK,check_express());
 949                 }
 950
 951         else if (!strncasecmp(cmdbuf,"QUIT",4)) {
 952                 cprintf("%d Goodbye.\n",OK);
 953                 CC->kill_me = 1;
 954                 }
 955
 956         else if (!strncasecmp(cmdbuf,"LOUT",4)) {
 957                 if (CC->logged_in) logout(CC);
 958                 cprintf("%d logged out.\n",OK);
 959                 }
 960
 961         else if (!strncasecmp(cmdbuf,"USER",4)) {
 962                 cmd_user(&cmdbuf[5]);
 963                 }
 964
 965         else if (!strncasecmp(cmdbuf,"PASS",4)) {
 966                 cmd_pass(&cmdbuf[5]);
 967                 }
 968
 969         else if (!strncasecmp(cmdbuf,"NEWU",4)) {
 970                 cmd_newu(&cmdbuf[5]);
 971                 }
 972
 973         else if (!strncasecmp(cmdbuf,"SETP",4)) {
 974                 cmd_setp(&cmdbuf[5]);
 975                 }
 976
 977         else if (!strncasecmp(cmdbuf,"LRMS",4)) {
 978                 cmd_lrms(&cmdbuf[5]);
 979                 }
 980
 981         else if (!strncasecmp(cmdbuf,"LKRA",4)) {
 982                 cmd_lkra(&cmdbuf[5]);
 983                 }
 984
 985         else if (!strncasecmp(cmdbuf,"LKRN",4)) {
 986                 cmd_lkrn(&cmdbuf[5]);
 987                 }
 988
 989         else if (!strncasecmp(cmdbuf,"LKRO",4)) {
 990                 cmd_lkro(&cmdbuf[5]);
 991                 }
 992
 993         else if (!strncasecmp(cmdbuf,"LZRM",4)) {
 994                 cmd_lzrm(&cmdbuf[5]);
 995                 }
 996
 997         else if (!strncasecmp(cmdbuf,"GETU",4)) {
 998                 cmd_getu();
 999                 }
1000
1001         else if (!strncasecmp(cmdbuf,"SETU",4)) {
1002                 cmd_setu(&cmdbuf[5]);
1003                 }
1004
1005         else if (!strncasecmp(cmdbuf,"GOTO",4)) {
1006                 cmd_goto(&cmdbuf[5]);
1007                 }
1008
1009         else if (!strncasecmp(cmdbuf,"MSGS",4)) {
1010                 cmd_msgs(&cmdbuf[5]);
1011                 }
1012
1013         else if (!strncasecmp(cmdbuf,"WHOK",4)) {
1014                 cmd_whok();
1015                 }
1016
1017         else if (!strncasecmp(cmdbuf,"RDIR",4)) {
1018                 cmd_rdir();
1019                 }
1020
1021         else if (!strncasecmp(cmdbuf,"MSG0",4)) {
1022                 cmd_msg0(&cmdbuf[5]);
1023                 }
1024
1025         else if (!strncasecmp(cmdbuf,"MSG2",4)) {
1026                 cmd_msg2(&cmdbuf[5]);
1027                 }
1028
1029         else if (!strncasecmp(cmdbuf,"MSG3",4)) {
1030                 cmd_msg3(&cmdbuf[5]);
1031                 }
1032
1033         else if (!strncasecmp(cmdbuf,"MSG4",4)) {
1034                 cmd_msg4(&cmdbuf[5]);
1035                 }
1036
1037         else if (!strncasecmp(cmdbuf,"OPNA",4)) {
1038                 cmd_opna(&cmdbuf[5]);
1039                 }
1040
1041         else if (!strncasecmp(cmdbuf,"INFO",4)) {
1042                 cmd_info();
1043                 }
1044
1045         else if (!strncasecmp(cmdbuf,"SLRP",4)) {
1046                 cmd_slrp(&cmdbuf[5]);
1047                 }
1048
1049         else if (!strncasecmp(cmdbuf,"INVT",4)) {
1050                 cmd_invt_kick(&cmdbuf[5],1);
1051                 }
1052
1053         else if (!strncasecmp(cmdbuf,"KICK",4)) {
1054                 cmd_invt_kick(&cmdbuf[5],0);
1055                 }
1056
1057         else if (!strncasecmp(cmdbuf,"GETR",4)) {
1058                 cmd_getr();
1059                 }
1060
1061         else if (!strncasecmp(cmdbuf,"SETR",4)) {
1062                 cmd_setr(&cmdbuf[5]);
1063                 }
1064
1065         else if (!strncasecmp(cmdbuf,"GETA",4)) {
1066                 cmd_geta();
1067                 }
1068
1069         else if (!strncasecmp(cmdbuf,"SETA",4)) {
1070                 cmd_seta(&cmdbuf[5]);
1071                 }
1072
1073         else if (!strncasecmp(cmdbuf,"ENT0",4)) {
1074                 cmd_ent0(&cmdbuf[5]);
1075                 }
1076
1077         else if (!strncasecmp(cmdbuf,"ENT3",4)) {
1078                 cmd_ent3(&cmdbuf[5]);
1079                 }
1080
1081         else if (!strncasecmp(cmdbuf,"RINF",4)) {
1082                 cmd_rinf();
1083                 }
1084
1085         else if (!strncasecmp(cmdbuf,"DELE",4)) {
1086                 cmd_dele(&cmdbuf[5]);
1087                 }
1088
1089         else if (!strncasecmp(cmdbuf,"KILL",4)) {
1090                 cmd_kill(&cmdbuf[5]);
1091                 }
1092
1093         else if (!strncasecmp(cmdbuf,"CRE8",4)) {
1094                 cmd_cre8(&cmdbuf[5]);
1095                 }
1096
1097         else if (!strncasecmp(cmdbuf,"MOVE",4)) {
1098                 cmd_move(&cmdbuf[5]);
1099                 }
1100
1101         else if (!strncasecmp(cmdbuf,"FORG",4)) {
1102                 cmd_forg();
1103                 }
1104
1105         else if (!strncasecmp(cmdbuf,"MESG",4)) {
1106                 cmd_mesg(&cmdbuf[5]);
1107                 }
1108
1109         else if (!strncasecmp(cmdbuf,"EMSG",4)) {
1110                 cmd_emsg(&cmdbuf[5]);
1111                 }
1112
1113         else if (!strncasecmp(cmdbuf,"GNUR",4)) {
1114                 cmd_gnur();
1115                 }
1116
1117         else if (!strncasecmp(cmdbuf,"VALI",4)) {
1118                 cmd_vali(&cmdbuf[5]);
1119                 }
1120
1121         else if (!strncasecmp(cmdbuf,"EINF",4)) {
1122                 cmd_einf(&cmdbuf[5]);
1123                 }
1124
1125         else if (!strncasecmp(cmdbuf,"LIST",4)) {
1126                 cmd_list();
1127                 }
1128
1129         else if (!strncasecmp(cmdbuf,"CHEK",4)) {
1130                 cmd_chek();
1131                 }
1132
1133         else if (!strncasecmp(cmdbuf,"DELF",4)) {
1134                 cmd_delf(&cmdbuf[5]);
1135                 }
1136
1137         else if (!strncasecmp(cmdbuf,"MOVF",4)) {
1138                 cmd_movf(&cmdbuf[5]);
1139                 }
1140
1141         else if (!strncasecmp(cmdbuf,"NETF",4)) {
1142                 cmd_netf(&cmdbuf[5]);
1143                 }
1144
1145         else if (!strncasecmp(cmdbuf,"RWHO",4)) {
1146                 cmd_rwho();
1147                 }
1148
1149         else if (!strncasecmp(cmdbuf,"OPEN",4)) {
1150                 cmd_open(&cmdbuf[5]);
1151                 }
1152
1153         else if (!strncasecmp(cmdbuf,"CLOS",4)) {
1154                 cmd_clos();
1155                 }
1156
1157         else if (!strncasecmp(cmdbuf,"UOPN",4)) {
1158                 cmd_uopn(&cmdbuf[5]);
1159                 }
1160
1161         else if (!strncasecmp(cmdbuf,"UCLS",4)) {
1162                 cmd_ucls(&cmdbuf[5]);
1163                 }
1164
1165         else if (!strncasecmp(cmdbuf,"READ",4)) {
1166                 cmd_read(&cmdbuf[5]);
1167                 }
1168
1169         else if (!strncasecmp(cmdbuf,"WRIT",4)) {
1170                 cmd_writ(&cmdbuf[5]);
1171                 }
1172
1173         else if (!strncasecmp(cmdbuf,"QUSR",4)) {
1174                 cmd_qusr(&cmdbuf[5]);
1175                 }
1176
1177         else if (!strncasecmp(cmdbuf,"ECHO",4)) {
1178                 cmd_echo(&cmdbuf[5]);
1179                 }
1180
1181         else if (!strncasecmp(cmdbuf,"OIMG",4)) {
1182                 cmd_oimg(&cmdbuf[5]);
1183                 }
1184
1185         else if (!strncasecmp(cmdbuf,"MORE",4)) {
1186                 cmd_more();
1187                 }
1188
1189         else if (!strncasecmp(cmdbuf,"NETP",4)) {
1190                 cmd_netp(&cmdbuf[5]);
1191                 }
1192
1193         else if (!strncasecmp(cmdbuf,"NDOP",4)) {
1194                 cmd_ndop(&cmdbuf[5]);
1195                 }
1196
1197         else if (!strncasecmp(cmdbuf,"NUOP",4)) {
1198                 cmd_nuop(&cmdbuf[5]);
1199                 }
1200
1201         else if (!strncasecmp(cmdbuf,"LFLR",4)) {
1202                 cmd_lflr();
1203                 }
1204
1205         else if (!strncasecmp(cmdbuf,"CFLR",4)) {
1206                 cmd_cflr(&cmdbuf[5]);
1207                 }
1208
1209         else if (!strncasecmp(cmdbuf,"KFLR",4)) {
1210                 cmd_kflr(&cmdbuf[5]);
1211                 }
1212
1213         else if (!strncasecmp(cmdbuf,"EFLR",4)) {
1214                 cmd_eflr(&cmdbuf[5]);
1215                 }
1216
1217         else if (!strncasecmp(cmdbuf,"IDEN",4)) {
1218                 cmd_iden(&cmdbuf[5]);
1219                 }
1220
1221         else if (!strncasecmp(cmdbuf,"IPGM",4)) {
1222                 cmd_ipgm(&cmdbuf[5]);
1223                 }
1224
1225         else if (!strncasecmp(cmdbuf,"EBIO",4)) {
1226                 cmd_ebio();
1227                 }
1228
1229         else if (!strncasecmp(cmdbuf,"RBIO",4)) {
1230                 cmd_rbio(&cmdbuf[5]);
1231                 }
1232
1233         else if (!strncasecmp(cmdbuf,"LBIO",4)) {
1234                 cmd_lbio();
1235                 }
1236
1237         else if (!strncasecmp(cmdbuf,"STEL",4)) {
1238                 cmd_stel(&cmdbuf[5]);
1239                 }
1240
1241         else if (!strncasecmp(cmdbuf,"TERM",4)) {
1242                 cmd_term(&cmdbuf[5]);
1243                 }
1244
1245         else if (!strncasecmp(cmdbuf,"DOWN",4)) {
1246                 cmd_down();
1247                 }
1248
1249         else if (!strncasecmp(cmdbuf,"SCDN",4)) {
1250                 cmd_scdn(&cmdbuf[5]);
1251                 }
1252
1253         else if (!strncasecmp(cmdbuf, "NSET", 4)) {
1254                 cmd_nset(&cmdbuf[5]);
1255                 }
1256
1257         else if (!strncasecmp(cmdbuf, "UIMG", 4)) {
1258                 cmd_uimg(&cmdbuf[5]);
1259                 }
1260
1261         else if (!strncasecmp(cmdbuf, "UCHG", 4)) {
1262                 cmd_uchg(&cmdbuf[5]);
1263                 }
1264
1265         else if (!strncasecmp(cmdbuf, "TIME", 4)) {
1266                 cmd_time();
1267                 }
1268
1269         else if (!strncasecmp(cmdbuf, "HCHG", 4)) {
1270                 cmd_hchg(&cmdbuf[5]);
1271                 }
1272
1273         else if (!strncasecmp(cmdbuf, "RCHG", 4)) {
1274                 cmd_rchg(&cmdbuf[5]);
1275                 }
1276
1277         else if (!strncasecmp(cmdbuf, "AGUP", 4)) {
1278                 cmd_agup(&cmdbuf[5]);
1279                 }
1280
1281         else if (!strncasecmp(cmdbuf, "ASUP", 4)) {
1282                 cmd_asup(&cmdbuf[5]);
1283                 }
1284
1285         else if (!strncasecmp(cmdbuf, "GPEX", 4)) {
1286                 cmd_gpex(&cmdbuf[5]);
1287                 }
1288
1289         else if (!strncasecmp(cmdbuf, "SPEX", 4)) {
1290                 cmd_spex(&cmdbuf[5]);
1291                 }
1292
1293         else if (!strncasecmp(cmdbuf, "CONF", 4)) {
1294                 cmd_conf(&cmdbuf[5]);
1295                 }
1296
1297 #ifdef DEBUG_MEMORY_LEAKS
1298         else if (!strncasecmp(cmdbuf, "LEAK", 4)) {
1299                 dump_tracked();
1300                 }
1301 #endif
1302
1303         else if (!DLoader_Exec_Cmd(cmdbuf))
1304                 {
1305                    cprintf("%d Unrecognized or unsupported command.\n",
1306                             ERROR);
1307                 }
1308
1309         /* Run any after-each-command outines registered by modules */
1310         PerformSessionHooks(EVT_CMD);
1311 }