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 #include <sys/types.h>
  19 #include <sys/stat.h>
  20
  21
  22 #if TIME_WITH_SYS_TIME
  23 # include <sys/time.h>
  24 # include <time.h>
  25 #else
  26 # if HAVE_SYS_TIME_H
  27 #  include <sys/time.h>
  28 # else
  29 #  include <time.h>
  30 # endif
  31 #endif
  32
  33 #include <ctype.h>
  34 #include <string.h>
  35 #include <errno.h>
  36 #include <limits.h>
  37 #include <syslog.h>
  38 /* #include <dlfcn.h> */
  39 #include <netdb.h>
  40 #include <sys/types.h>
  41 #include <sys/socket.h>
  42 #include <netinet/in.h>
  43 #include <arpa/inet.h>
  44 #include "citadel.h"
  45 #include "server.h"
  46 #include "serv_extensions.h"
  47 #include "sysdep_decls.h"
  48 #include "citserver.h"
  49 #include "config.h"
  50 #include "database.h"
  51 #include "housekeeping.h"
  52 #include "user_ops.h"
  53 #include "msgbase.h"
  54 #include "support.h"
  55 #include "locate_host.h"
  56 #include "room_ops.h"
  57 #include "file_ops.h"
  58 #include "policy.h"
  59 #include "control.h"
  60 #include "tools.h"
  61
  62 #ifndef HAVE_SNPRINTF
  63 #include "snprintf.h"
  64 #endif
  65
  66 struct CitContext *ContextList = NULL;
  67 char *unique_session_numbers;
  68 int ScheduledShutdown = 0;
  69 int do_defrag = 0;
  70 time_t server_startup_time;
  71
  72 /*
  73  * Various things that need to be initialized at startup
  74  */
  75 void master_startup(void) {
  76         struct timeval tv;
  77         struct ctdlroom qrbuf;
  78
  79         lprintf(9, "master_startup() started\n");
  80         time(&server_startup_time);
  81
  82         lprintf(7, "Opening databases\n");
  83         open_databases();
  84
  85         if (do_defrag) {
  86                 defrag_databases();
  87         }
  88
  89         check_ref_counts();
  90
  91         lprintf(7, "Creating base rooms (if necessary)\n");
  92         create_room(BASEROOM,           0, "", 0, 1, 0);
  93         create_room(AIDEROOM,           3, "", 0, 1, 0);
  94         create_room(SYSCONFIGROOM,      3, "", 0, 1, 0);
  95         create_room(config.c_twitroom,  0, "", 0, 1, 0);
  96
  97         /* The "Local System Configuration" room doesn't need to be visible */
  98         if (lgetroom(&qrbuf, SYSCONFIGROOM) == 0) {
  99                 qrbuf.QRflags2 |= QR2_SYSTEM;
 100                 lputroom(&qrbuf);
 101         }
 102
 103
 104         lprintf(7, "Seeding the pseudo-random number generator...\n");
 105         gettimeofday(&tv, NULL);
 106         srand(tv.tv_usec);
 107         lprintf(9, "master_startup() finished\n");
 108 }
 109
 110
 111
 112 /*
 113  * Cleanup routine to be called when the server is shutting down.
 114  * WARNING: It's no longer safe to call this function to force a shutdown.
 115  * Instead, set time_to_die = 1.
 116  */
 117 void master_cleanup(void) {
 118         struct CleanupFunctionHook *fcn;
 119
 120         /* Run any cleanup routines registered by loadable modules */
 121         for (fcn = CleanupHookTable; fcn != NULL; fcn = fcn->next) {
 122                 (*fcn->h_function_pointer)();
 123         }
 124
 125         /* Close databases */
 126         lprintf(7, "Closing databases\n");
 127         close_databases();
 128
 129         /* Do system-dependent stuff */
 130         sysdep_master_cleanup();
 131
 132         /* Now go away. */
 133         lprintf(3, "citserver: exiting.\n");
 134         fflush(stdout); fflush(stderr);
 135         exit(0);
 136 }
 137
 138
 139 /*
 140  * Free any per-session data allocated by modules or whatever
 141  */
 142 void deallocate_user_data(struct CitContext *con)
 143 {
 144         struct CtdlSessData *ptr;
 145
 146         begin_critical_section(S_SESSION_TABLE);
 147         while (con->FirstSessData != NULL) {
 148                 lprintf(9, "Deallocating user data symbol %ld\n",
 149                         con->FirstSessData->sym_id);
 150                 if (con->FirstSessData->sym_data != NULL)
 151                         phree(con->FirstSessData->sym_data);
 152                 ptr = con->FirstSessData->next;
 153                 phree(con->FirstSessData);
 154                 con->FirstSessData = ptr;
 155         }
 156         end_critical_section(S_SESSION_TABLE);
 157 }
 158
 159
 160
 161
 162 /*
 163  * Terminate a session and remove its context data structure.
 164  */
 165 void RemoveContext (struct CitContext *con)
 166 {
 167         struct CitContext *ptr = NULL;
 168         struct CitContext *ToFree = NULL;
 169
 170         lprintf(9, "RemoveContext() called\n");
 171         if (con==NULL) {
 172                 lprintf(5, "WARNING: RemoveContext() called with NULL!\n");
 173                 return;
 174         }
 175
 176         /* Remove the context from the global context list.  This needs
 177          * to get done FIRST to avoid concurrency problems.  It is *vitally*
 178          * important to keep num_sessions accurate!!
 179          */
 180         lprintf(7, "Removing context for session %d\n", con->cs_pid);
 181         begin_critical_section(S_SESSION_TABLE);
 182         if (ContextList == con) {
 183                 ToFree = ContextList;
 184                 ContextList = ContextList->next;
 185                 --num_sessions;
 186         }
 187         else {
 188                 for (ptr = ContextList; ptr != NULL; ptr = ptr->next) {
 189                         if (ptr->next == con) {
 190                                 ToFree = ptr->next;
 191                                 ptr->next = ptr->next->next;
 192                                 --num_sessions;
 193                         }
 194                 }
 195         }
 196         end_critical_section(S_SESSION_TABLE);
 197
 198         if (ToFree == NULL) {
 199                 lprintf(9, "RemoveContext() found nothing to remove\n");
 200                 return;
 201         }
 202
 203         /* Run any cleanup routines registered by loadable modules.
 204          * Note 1: This must occur *before* deallocate_user_data() because the
 205          *         cleanup functions might touch dynamic session data.
 206          * Note 2: We have to "become_session()" because the cleanup functions
 207          *         might make references to "CC" assuming it's the right one.
 208          */
 209         become_session(con);
 210         PerformSessionHooks(EVT_STOP);
 211         become_session(NULL);
 212
 213         /* Now handle all of the administrivia. */
 214         lprintf(7, "Calling logout(%d)\n", con->cs_pid);
 215         logout(con);
 216
 217         unlink(con->temp);
 218         lprintf(3, "[%3d] Session ended.\n", con->cs_pid);
 219         syslog(LOG_NOTICE,"session %d: ended", con->cs_pid);
 220
 221         /* Deallocate any user-data attached to this session */
 222         deallocate_user_data(con);
 223
 224         /* If the client is still connected, blow 'em away. */
 225         lprintf(7, "Closing socket %d\n", con->client_socket);
 226         close(con->client_socket);
 227
 228         /* This is where we used to check for scheduled shutdowns. */
 229
 230         /* Free up the memory used by this context */
 231         phree(con);
 232
 233         lprintf(7, "Done with RemoveContext()\n");
 234 }
 235
 236
 237
 238 /*
 239  * Get a dynamic symbol number for per-session user data.
 240  * This API call should be made only ONCE per symbol per citserver run.
 241  */
 242 int CtdlGetDynamicSymbol()
 243 {
 244         static unsigned int next_symbol = SYM_MAX;
 245         return ++next_symbol;
 246 }
 247
 248
 249
 250 /*
 251  * Return a pointer to some generic per-session user data.
 252  * (This function returns NULL if the requested symbol is not allocated.)
 253  *
 254  * NOTE: we use critical sections for allocating and de-allocating these,
 255  *       but not for locating one.
 256  */
 257 void *CtdlGetUserData(unsigned long requested_sym)
 258 {
 259         struct CtdlSessData *ptr;
 260
 261         for (ptr = CC->FirstSessData; ptr != NULL; ptr = ptr->next)
 262                 if (ptr->sym_id == requested_sym)
 263                         return(ptr->sym_data);
 264
 265         lprintf(2, "ERROR! CtdlGetUserData(%ld) symbol not allocated\n",
 266                 requested_sym);
 267         return NULL;
 268 }
 269
 270
 271 /*
 272  * Allocate some generic per-session user data.
 273  */
 274 void CtdlAllocUserData(unsigned long requested_sym, size_t num_bytes)
 275 {
 276         struct CtdlSessData *ptr;
 277
 278         lprintf(9, "CtdlAllocUserData(%ld) called\n", requested_sym);
 279
 280         /* Fail silently if the symbol is already registered. */
 281         for (ptr = CC->FirstSessData; ptr != NULL; ptr = ptr->next)  {
 282                 if (ptr->sym_id == requested_sym) {
 283                         return;
 284                 }
 285         }
 286
 287         /* Grab us some memory!  Dem's good eatin' !!  */
 288         ptr = mallok(sizeof(struct CtdlSessData));
 289         ptr->sym_id = requested_sym;
 290         ptr->sym_data = mallok(num_bytes);
 291         memset(ptr->sym_data, 0, num_bytes);
 292
 293         begin_critical_section(S_SESSION_TABLE);
 294         ptr->next = CC->FirstSessData;
 295         CC->FirstSessData = ptr;
 296         end_critical_section(S_SESSION_TABLE);
 297
 298         lprintf(9, "CtdlAllocUserData(%ld) finished\n", requested_sym);
 299 }
 300
 301
 302 /*
 303  * Change the size of a buffer allocated with CtdlAllocUserData()
 304  */
 305 void CtdlReallocUserData(unsigned long requested_sym, size_t num_bytes)
 306 {
 307         struct CtdlSessData *ptr;
 308
 309         for (ptr = CC->FirstSessData; ptr != NULL; ptr = ptr->next)  {
 310                 if (ptr->sym_id == requested_sym) {
 311                         ptr->sym_data = reallok(ptr->sym_data, num_bytes);
 312                         return;
 313                 }
 314         }
 315
 316         lprintf(2, "CtdlReallocUserData() ERROR: symbol %ld not found!\n",
 317                 requested_sym);
 318 }
 319
 320
 321
 322
 323
 324
 325 /*
 326  * cmd_info()  -  tell the client about this server
 327  */
 328 void cmd_info(void) {
 329         cprintf("%d Server info:\n", LISTING_FOLLOWS);
 330         cprintf("%d\n", CC->cs_pid);
 331         cprintf("%s\n", config.c_nodename);
 332         cprintf("%s\n", config.c_humannode);
 333         cprintf("%s\n", config.c_fqdn);
 334         cprintf("%s\n", CITADEL);
 335         cprintf("%d\n", REV_LEVEL);
 336         cprintf("%s\n", config.c_bbs_city);
 337         cprintf("%s\n", config.c_sysadm);
 338         cprintf("%d\n", SERVER_TYPE);
 339         cprintf("%s\n", config.c_moreprompt);
 340         cprintf("1\n"); /* 1 = yes, this system supports floors */
 341         cprintf("1\n"); /* 1 = we support the extended paging options */
 342         cprintf("%s\n", CC->cs_nonce);
 343         cprintf("1\n"); /* 1 = yes, this system supports the QNOP command */
 344         cprintf("000\n");
 345 }
 346
 347
 348 /*
 349  * returns an asterisk if there are any express messages waiting,
 350  * space otherwise.
 351  */
 352 char CtdlCheckExpress(void) {
 353         if (CC->FirstExpressMessage == NULL) {
 354                 return(' ');
 355         }
 356         else {
 357                 return('*');
 358         }
 359 }
 360
 361 void cmd_time(void)
 362 {
 363    time_t tv;
 364    struct tm *tmp;
 365
 366    tv = time(NULL);
 367    tmp = localtime(&tv);
 368
 369    /* timezone and daylight global variables are not portable. */
 370 #ifdef HAVE_STRUCT_TM_TM_GMTOFF
 371    cprintf("%d %ld|%ld|%d\n", CIT_OK, (long)tv, tmp->tm_gmtoff, tmp->tm_isdst);
 372 #else
 373    cprintf("%d %ld|%ld|%d\n", CIT_OK, (long)tv, timezone, tmp->tm_isdst);
 374 #endif
 375 }
 376
 377
 378 /*
 379  * Check originating host against the public_clients file.  This determines
 380  * whether the client is allowed to change the hostname for this session
 381  * (for example, to show the location of the user rather than the location
 382  * of the client).
 383  */
 384 int is_public_client(void)
 385 {
 386         char buf[SIZ];
 387         char addrbuf[SIZ];
 388         FILE *fp;
 389         int i;
 390         struct stat statbuf;
 391         static time_t pc_timestamp = 0;
 392         static char public_clients[SIZ];
 393
 394 #define PUBLIC_CLIENTS "./public_clients"
 395
 396         /*
 397          * Check the time stamp on the public_clients file.  If it's been
 398          * updated since the last time we were here (or if this is the first
 399          * time we've been through the loop), read its contents and learn
 400          * the IP addresses of the listed hosts.
 401          */
 402         if (stat(PUBLIC_CLIENTS, &statbuf) != 0) {
 403                 /* No public_clients file exists, so bail out */
 404                 lprintf(5, "Warning: '%s' does not exist\n", PUBLIC_CLIENTS);
 405                 return(0);
 406         }
 407
 408         if (statbuf.st_mtime > pc_timestamp) {
 409                 begin_critical_section(S_PUBLIC_CLIENTS);
 410                 lprintf(7, "Loading %s\n", PUBLIC_CLIENTS);
 411
 412                 strcpy(public_clients, "127.0.0.1");
 413                 if (hostname_to_dotted_quad(addrbuf, config.c_fqdn) == 0) {
 414                         strcat(public_clients, "|");
 415                         strcat(public_clients, addrbuf);
 416                 }
 417
 418                 fp = fopen("public_clients", "r");
 419                 if (fp != NULL) while (fgets(buf, sizeof buf, fp)!=NULL) {
 420                         for (i=0; i<strlen(buf); ++i) {
 421                                 if (buf[i] == '#') buf[i] = 0;
 422                         }
 423                         while (isspace((buf[strlen(buf)-1]))) {
 424                                 buf[strlen(buf)-1] = 0;
 425                         }
 426                         if (hostname_to_dotted_quad(addrbuf, buf) == 0) {
 427                                 if ((strlen(public_clients) +
 428                                    strlen(addrbuf) + 2)
 429                                    < sizeof(public_clients)) {
 430                                         strcat(public_clients, addrbuf);
 431                                 }
 432                         }
 433                 }
 434                 fclose(fp);
 435                 pc_timestamp = time(NULL);
 436                 end_critical_section(S_PUBLIC_CLIENTS);
 437         }
 438
 439         lprintf(9, "Checking whether %s is a local or public client\n",
 440                 CC->cs_addr);
 441         for (i=0; i<num_parms(public_clients); ++i) {
 442                 extract(addrbuf, public_clients, i);
 443                 if (!strcasecmp(CC->cs_addr, addrbuf)) {
 444                         lprintf(9, "... yes it is.\n");
 445                         return(1);
 446                 }
 447         }
 448
 449         /* No hits.  This is not a public client. */
 450         lprintf(9, "... no it isn't.\n");
 451         return(0);
 452 }
 453
 454
 455 /*
 456  * the client is identifying itself to the server
 457  */
 458 void cmd_iden(char *argbuf)
 459 {
 460         int dev_code;
 461         int cli_code;
 462         int rev_level;
 463         char desc[SIZ];
 464         char from_host[SIZ];
 465         struct in_addr addr;
 466         int do_lookup = 0;
 467
 468         if (num_parms(argbuf)<4) {
 469                 cprintf("%d usage error\n",ERROR);
 470                 return;
 471         }
 472
 473         dev_code = extract_int(argbuf,0);
 474         cli_code = extract_int(argbuf,1);
 475         rev_level = extract_int(argbuf,2);
 476         extract(desc,argbuf,3);
 477
 478         safestrncpy(from_host, config.c_fqdn, sizeof from_host);
 479         from_host[sizeof from_host - 1] = 0;
 480         if (num_parms(argbuf)>=5) extract(from_host,argbuf,4);
 481
 482         CC->cs_clientdev = dev_code;
 483         CC->cs_clienttyp = cli_code;
 484         CC->cs_clientver = rev_level;
 485         safestrncpy(CC->cs_clientname, desc, sizeof CC->cs_clientname);
 486         CC->cs_clientname[31] = 0;
 487
 488         if (strlen(from_host) > 0) {
 489                 if (CC->is_local_socket) do_lookup = 1;
 490                 else if (is_public_client()) do_lookup = 1;
 491         }
 492
 493         if (do_lookup) {
 494                 lprintf(9, "Looking up hostname '%s'\n", from_host);
 495                 if ((addr.s_addr = inet_addr(from_host)) != -1) {
 496                         locate_host(CC->cs_host, sizeof CC->cs_host,
 497                                 NULL, 0,
 498                                 &addr);
 499                 }
 500                 else {
 501                         safestrncpy(CC->cs_host, from_host, sizeof CC->cs_host);
 502                         CC->cs_host[sizeof CC->cs_host - 1] = 0;
 503                 }
 504         }
 505
 506         lprintf(7, "client %d/%d/%01d.%02d (%s)\n",
 507                 dev_code,
 508                 cli_code,
 509                 (rev_level / 100),
 510                 (rev_level % 100),
 511                 desc);
 512
 513         syslog(LOG_NOTICE,"session %d: client %d/%d/%01d.%02d (%s) from %s\n",
 514                 CC->cs_pid,
 515                 dev_code,
 516                 cli_code,
 517                 (rev_level / 100),
 518                 (rev_level % 100),
 519                 desc,
 520                 CC->cs_host);
 521         cprintf("%d Ok\n",CIT_OK);
 522 }
 523
 524
 525 /*
 526  * display system messages or help
 527  */
 528 void cmd_mesg(char *mname)
 529 {
 530         FILE *mfp;
 531         char targ[SIZ];
 532         char buf[SIZ];
 533         char buf2[SIZ];
 534         char *dirs[2];
 535
 536         extract(buf,mname,0);
 537
 538         dirs[0]=mallok(64);
 539         dirs[1]=mallok(64);
 540         strcpy(dirs[0],"messages");
 541         strcpy(dirs[1],"help");
 542         snprintf(buf2, sizeof buf2, "%s.%d.%d", buf, CC->cs_clientdev, CC->cs_clienttyp);
 543         mesg_locate(targ,sizeof targ,buf2,2,(const char **)dirs);
 544         if (strlen(targ) == 0) {
 545                 snprintf(buf2, sizeof buf2, "%s.%d", buf, CC->cs_clientdev);
 546                 mesg_locate(targ,sizeof targ,buf2,2,(const char **)dirs);
 547                 if (strlen(targ) == 0) {
 548                         mesg_locate(targ,sizeof targ,buf,2,(const char **)dirs);
 549                 }
 550         }
 551         phree(dirs[0]);
 552         phree(dirs[1]);
 553
 554         if (strlen(targ)==0) {
 555                 cprintf("%d '%s' not found.\n",ERROR,mname);
 556                 return;
 557         }
 558
 559         mfp = fopen(targ,"r");
 560         if (mfp==NULL) {
 561                 cprintf("%d Cannot open '%s': %s\n",
 562                         ERROR,targ,strerror(errno));
 563                 return;
 564         }
 565         cprintf("%d %s\n",LISTING_FOLLOWS,buf);
 566
 567         while (fgets(buf, (SIZ-1), mfp)!=NULL) {
 568                 buf[strlen(buf)-1] = 0;
 569                 do_help_subst(buf);
 570                 cprintf("%s\n",buf);
 571         }
 572
 573         fclose(mfp);
 574         cprintf("000\n");
 575 }
 576
 577
 578 /*
 579  * enter system messages or help
 580  */
 581 void cmd_emsg(char *mname)
 582 {
 583         FILE *mfp;
 584         char targ[SIZ];
 585         char buf[SIZ];
 586         char *dirs[2];
 587         int a;
 588
 589         if (CtdlAccessCheck(ac_aide)) return;
 590
 591         extract(buf,mname,0);
 592         for (a=0; a<strlen(buf); ++a) {         /* security measure */
 593                 if (buf[a] == '/') buf[a] = '.';
 594         }
 595
 596         dirs[0]=mallok(64);
 597         dirs[1]=mallok(64);
 598         strcpy(dirs[0],"messages");
 599         strcpy(dirs[1],"help");
 600         mesg_locate(targ,sizeof targ,buf,2,(const char**)dirs);
 601         phree(dirs[0]);
 602         phree(dirs[1]);
 603
 604         if (strlen(targ)==0) {
 605                 snprintf(targ, sizeof targ, "./help/%s", buf);
 606         }
 607
 608         mfp = fopen(targ,"w");
 609         if (mfp==NULL) {
 610                 cprintf("%d Cannot open '%s': %s\n",
 611                         ERROR,targ,strerror(errno));
 612                 return;
 613         }
 614         cprintf("%d %s\n", SEND_LISTING, targ);
 615
 616         while (client_gets(buf), strcmp(buf, "000")) {
 617                 fprintf(mfp, "%s\n", buf);
 618         }
 619
 620         fclose(mfp);
 621 }
 622
 623
 624 /* Don't show the names of private rooms unless the viewing
 625  * user also knows the rooms.
 626  */
 627 void GenerateRoomDisplay(char *real_room,
 628                         struct CitContext *viewed,
 629                         struct CitContext *viewer) {
 630
 631         strcpy(real_room, viewed->room.QRname);
 632         if (viewed->room.QRflags & QR_MAILBOX) {
 633                 strcpy(real_room, &real_room[11]);
 634         }
 635         if (viewed->room.QRflags & QR_PRIVATE) {
 636                 if ( (CtdlRoomAccess(&viewed->room, &viewer->user)
 637                    & UA_KNOWN) == 0) {
 638                         strcpy(real_room, "<private room>");
 639                 }
 640         }
 641
 642         if (viewed->cs_flags & CS_CHAT) {
 643                 while (strlen(real_room) < 14)
 644                         strcat(real_room, " ");
 645
 646                 strcpy(&real_room[14], "<chat>");
 647         }
 648
 649 }
 650
 651 /*
 652  * Convenience function.
 653  */
 654 int CtdlAccessCheck(int required_level) {
 655
 656         if (CC->internal_pgm) return(0);
 657         if (required_level >= ac_internal) {
 658                 cprintf("%d This is not a user-level command.\n",
 659                         ERROR+HIGHER_ACCESS_REQUIRED);
 660                 return(-1);
 661         }
 662
 663         if (CC->user.axlevel >= 6) return(0);
 664         if (required_level >= ac_aide) {
 665                 cprintf("%d This command requires Aide access.\n",
 666                         ERROR+HIGHER_ACCESS_REQUIRED);
 667                 return(-1);
 668         }
 669
 670         if (is_room_aide()) return(0);
 671         if (required_level >= ac_room_aide) {
 672                 cprintf("%d This command requires Aide or Room Aide access.\n",
 673                         ERROR + HIGHER_ACCESS_REQUIRED);
 674                 return(-1);
 675         }
 676
 677         if (CC->logged_in) return(0);
 678         if (required_level >= ac_logged_in) {
 679                 cprintf("%d Not logged in.\n", ERROR+NOT_LOGGED_IN);
 680                 return(-1);
 681         }
 682
 683         /* shhh ... succeed quietly */
 684         return(0);
 685 }
 686
 687
 688
 689 /*
 690  * Terminate another running session
 691  */
 692 void cmd_term(char *cmdbuf)
 693 {
 694         int session_num;
 695         struct CitContext *ccptr;
 696         int found_it = 0;
 697         int allowed = 0;
 698
 699         session_num = extract_int(cmdbuf, 0);
 700         if (session_num == CC->cs_pid) {
 701                 cprintf("%d You can't kill your own session.\n", ERROR);
 702                 return;
 703         }
 704
 705         lprintf(9, "Locating session to kill\n");
 706         begin_critical_section(S_SESSION_TABLE);
 707         for (ccptr = ContextList; ccptr != NULL; ccptr = ccptr->next) {
 708                 if (session_num == ccptr->cs_pid) {
 709                         found_it = 1;
 710                         if ((ccptr->user.usernum == CC->user.usernum)
 711                            || (CC->user.axlevel >= 6)) {
 712                                 allowed = 1;
 713                                 ccptr->kill_me = 1;
 714                         }
 715                         else {
 716                                 allowed = 0;
 717                         }
 718                 }
 719         }
 720         end_critical_section(S_SESSION_TABLE);
 721
 722         if (found_it) {
 723                 if (allowed) {
 724                         cprintf("%d Session terminated.\n", CIT_OK);
 725                 }
 726                 else {
 727                         cprintf("%d You are not allowed to do that.\n",
 728                                 ERROR + HIGHER_ACCESS_REQUIRED);
 729                 }
 730         }
 731         else {
 732                 cprintf("%d No such session.\n", ERROR);
 733         }
 734 }
 735
 736
 737
 738
 739
 740 /*
 741  * get the paginator prompt
 742  */
 743 void cmd_more(void) {
 744         cprintf("%d %s\n", CIT_OK, config.c_moreprompt);
 745 }
 746
 747 /*
 748  * echo
 749  */
 750 void cmd_echo(char *etext)
 751 {
 752         cprintf("%d %s\n", CIT_OK, etext);
 753 }
 754
 755
 756
 757 /*
 758  * identify as internal program
 759  */
 760 void cmd_ipgm(char *argbuf)
 761 {
 762         int secret;
 763
 764         secret = extract_int(argbuf, 0);
 765         if (secret == config.c_ipgm_secret) {
 766                 CC->internal_pgm = 1;
 767                 strcpy(CC->curr_user, "<internal program>");
 768                 CC->cs_flags = CC->cs_flags|CS_STEALTH;
 769                 cprintf("%d Authenticated as an internal program.\n",CIT_OK);
 770         }
 771         else {
 772                 cprintf("%d Authentication failed.\n",ERROR);
 773                 lprintf(3, "Warning: ipgm authentication failed.\n");
 774         }
 775 }
 776
 777
 778 /*
 779  * Shut down the server
 780  */
 781 void cmd_down(void) {
 782
 783         if (CtdlAccessCheck(ac_aide)) return;
 784
 785         cprintf("%d Shutting down server.  Goodbye.\n", CIT_OK);
 786         time_to_die = 1;
 787 }
 788
 789 /*
 790  * Schedule or cancel a server shutdown
 791  */
 792 void cmd_scdn(char *argbuf)
 793 {
 794         int new_state;
 795
 796         if (CtdlAccessCheck(ac_aide)) return;
 797
 798         new_state = extract_int(argbuf, 0);
 799         if ((new_state == 0) || (new_state == 1)) {
 800                 ScheduledShutdown = new_state;
 801         }
 802         cprintf("%d %d\n", CIT_OK, ScheduledShutdown);
 803 }
 804
 805
 806 /*
 807  * Set or unset asynchronous protocol mode
 808  */
 809 void cmd_asyn(char *argbuf)
 810 {
 811         int new_state;
 812
 813         new_state = extract_int(argbuf, 0);
 814         if ((new_state == 0) || (new_state == 1)) {
 815                 CC->is_async = new_state;
 816         }
 817         cprintf("%d %d\n", CIT_OK, CC->is_async);
 818 }
 819
 820
 821 /*
 822  * Generate a "nonce" for APOP-style authentication.
 823  *
 824  * RFC 1725 et al specify a PID to be placed in front of the nonce.
 825  * Quoth BTX: That would be stupid.
 826  */
 827 void generate_nonce(struct CitContext *con) {
 828         struct timeval tv;
 829
 830         memset(con->cs_nonce, NONCE_SIZE, 0);
 831         gettimeofday(&tv, NULL);
 832         memset(con->cs_nonce, NONCE_SIZE, 0);
 833         snprintf(con->cs_nonce, NONCE_SIZE, "<%d%ld@%s>",
 834                 rand(), (long)tv.tv_usec, config.c_fqdn);
 835 }
 836
 837
 838
 839
 840 /*
 841  * Back-end function for starting a session
 842  */
 843 void begin_session(struct CitContext *con)
 844 {
 845         int len;        /* should be socklen_t but doesn't work on Macintosh */
 846         struct sockaddr_in sin;
 847
 848         /*
 849          * Initialize some variables specific to our context.
 850          */
 851         con->logged_in = 0;
 852         con->internal_pgm = 0;
 853         con->download_fp = NULL;
 854         con->upload_fp = NULL;
 855         con->FirstExpressMessage = NULL;
 856         time(&con->lastcmd);
 857         time(&con->lastidle);
 858         strcpy(con->lastcmdname, "    ");
 859         strcpy(con->cs_clientname, "(unknown)");
 860         strcpy(con->curr_user, NLI);
 861         strcpy(con->net_node,"");
 862         strcpy(con->fake_username, "");
 863         strcpy(con->fake_postname, "");
 864         strcpy(con->fake_hostname, "");
 865         strcpy(con->fake_roomname, "");
 866         generate_nonce(con);
 867         snprintf(con->temp, sizeof con->temp, tmpnam(NULL));
 868         safestrncpy(con->cs_host, config.c_fqdn, sizeof con->cs_host);
 869         safestrncpy(con->cs_addr, "", sizeof con->cs_addr);
 870         con->cs_host[sizeof con->cs_host - 1] = 0;
 871         len = sizeof sin;
 872         if (!CC->is_local_socket) {
 873                 if (!getpeername(con->client_socket,
 874                    (struct sockaddr *) &sin, &len))
 875                         locate_host(con->cs_host, sizeof con->cs_host,
 876                                 con->cs_addr, sizeof con->cs_addr,
 877                                 &sin.sin_addr);
 878         }
 879         else {
 880                 strcpy(con->cs_host, "");
 881         }
 882         con->cs_flags = 0;
 883         con->upload_type = UPL_FILE;
 884         con->dl_is_net = 0;
 885         con->FirstSessData = NULL;
 886
 887         con->nologin = 0;
 888         if ((config.c_maxsessions > 0)&&(num_sessions > config.c_maxsessions))
 889                 con->nologin = 1;
 890
 891         lprintf(3, "Session started.\n");
 892         syslog(LOG_NOTICE,"session %d: ended", con->cs_pid);
 893
 894         /* Run any session startup routines registered by loadable modules */
 895         PerformSessionHooks(EVT_START);
 896 }
 897
 898
 899 void citproto_begin_session() {
 900         if (CC->nologin==1) {
 901                 cprintf("%d %s: Too many users are already online "
 902                         "(maximum is %d)\n",
 903                         ERROR+MAX_SESSIONS_EXCEEDED,
 904                         config.c_nodename, config.c_maxsessions);
 905         }
 906         else {
 907                 cprintf("%d %s Citadel/UX server ready.\n",
 908                         CIT_OK, config.c_nodename);
 909         }
 910 }
 911
 912
 913
 914
 915 /*
 916  * This loop recognizes all server commands.
 917  */
 918 void do_command_loop(void) {
 919         char cmdbuf[SIZ];
 920
 921         time(&CC->lastcmd);
 922         memset(cmdbuf, 0, sizeof cmdbuf); /* Clear it, just in case */
 923         if (client_gets(cmdbuf) < 1) {
 924                 lprintf(3, "Client socket is broken.  Ending session.\n");
 925                 CC->kill_me = 1;
 926                 return;
 927         }
 928         lprintf(5, "Citadel: %s\n", cmdbuf);
 929
 930         /*
 931          * Let other clients see the last command we executed, and
 932          * update the idle time, but not NOOP, QNOP, PEXP, or GEXP.
 933          */
 934         if ( (strncasecmp(cmdbuf, "NOOP", 4))
 935            && (strncasecmp(cmdbuf, "QNOP", 4))
 936            && (strncasecmp(cmdbuf, "PEXP", 4))
 937            && (strncasecmp(cmdbuf, "GEXP", 4)) ) {
 938                 strcpy(CC->lastcmdname, "    ");
 939                 safestrncpy(CC->lastcmdname, cmdbuf,
 940                         sizeof(CC->lastcmdname) );
 941                 time(&CC->lastidle);
 942         }
 943
 944         if ((strncasecmp(cmdbuf, "ENT0", 4))
 945            && (strncasecmp(cmdbuf, "MESG", 4))
 946            && (strncasecmp(cmdbuf, "MSGS", 4)))
 947         {
 948            CC->cs_flags &= ~CS_POSTING;
 949         }
 950
 951         if (!strncasecmp(cmdbuf,"NOOP",4)) {
 952                 cprintf("%d%cok\n",CIT_OK,CtdlCheckExpress());
 953         }
 954
 955         else if (!strncasecmp(cmdbuf,"QNOP",4)) {
 956                 /* do nothing, this command returns no response */
 957         }
 958
 959         else if (!strncasecmp(cmdbuf,"QUIT",4)) {
 960                 cprintf("%d Goodbye.\n",CIT_OK);
 961                 CC->kill_me = 1;
 962         }
 963
 964         else if (!strncasecmp(cmdbuf,"ASYN",4)) {
 965                 cmd_asyn(&cmdbuf[5]);
 966         }
 967
 968         else if (!strncasecmp(cmdbuf,"LOUT",4)) {
 969                 if (CC->logged_in) logout(CC);
 970                 cprintf("%d logged out.\n",CIT_OK);
 971         }
 972
 973         else if (!strncasecmp(cmdbuf,"USER",4)) {
 974                 cmd_user(&cmdbuf[5]);
 975         }
 976
 977         else if (!strncasecmp(cmdbuf,"PASS",4)) {
 978                 cmd_pass(&cmdbuf[5]);
 979         }
 980
 981         else if (!strncasecmp(cmdbuf,"NEWU",4)) {
 982                 cmd_newu(&cmdbuf[5]);
 983         }
 984
 985         else if (!strncasecmp(cmdbuf,"CREU",4)) {
 986                 cmd_creu(&cmdbuf[5]);
 987         }
 988
 989         else if (!strncasecmp(cmdbuf,"SETP",4)) {
 990                 cmd_setp(&cmdbuf[5]);
 991         }
 992
 993         else if (!strncasecmp(cmdbuf,"LRMS",4)) {
 994                 cmd_lrms(&cmdbuf[5]);
 995         }
 996
 997         else if (!strncasecmp(cmdbuf,"LKRA",4)) {
 998                 cmd_lkra(&cmdbuf[5]);
 999         }
1000
1001         else if (!strncasecmp(cmdbuf,"LKRN",4)) {
1002                 cmd_lkrn(&cmdbuf[5]);
1003         }
1004
1005         else if (!strncasecmp(cmdbuf,"LKRO",4)) {
1006                 cmd_lkro(&cmdbuf[5]);
1007         }
1008
1009         else if (!strncasecmp(cmdbuf,"LZRM",4)) {
1010                 cmd_lzrm(&cmdbuf[5]);
1011         }
1012
1013         else if (!strncasecmp(cmdbuf,"LPRM",4)) {
1014                 cmd_lprm(&cmdbuf[5]);
1015         }
1016
1017         else if (!strncasecmp(cmdbuf,"GETU",4)) {
1018                 cmd_getu();
1019         }
1020
1021         else if (!strncasecmp(cmdbuf,"SETU",4)) {
1022                 cmd_setu(&cmdbuf[5]);
1023         }
1024
1025         else if (!strncasecmp(cmdbuf,"GOTO",4)) {
1026                 cmd_goto(&cmdbuf[5]);
1027         }
1028
1029         else if (!strncasecmp(cmdbuf,"MSGS",4)) {
1030                 cmd_msgs(&cmdbuf[5]);
1031         }
1032
1033         else if (!strncasecmp(cmdbuf,"WHOK",4)) {
1034                 cmd_whok();
1035         }
1036
1037         else if (!strncasecmp(cmdbuf,"RDIR",4)) {
1038                 cmd_rdir();
1039         }
1040
1041         else if (!strncasecmp(cmdbuf,"MSG0",4)) {
1042                 cmd_msg0(&cmdbuf[5]);
1043         }
1044
1045         else if (!strncasecmp(cmdbuf,"MSG2",4)) {
1046                 cmd_msg2(&cmdbuf[5]);
1047         }
1048
1049         else if (!strncasecmp(cmdbuf,"MSG3",4)) {
1050                 cmd_msg3(&cmdbuf[5]);
1051         }
1052
1053         else if (!strncasecmp(cmdbuf,"MSG4",4)) {
1054                 cmd_msg4(&cmdbuf[5]);
1055         }
1056
1057         else if (!strncasecmp(cmdbuf,"MSGP",4)) {
1058                 cmd_msgp(&cmdbuf[5]);
1059         }
1060
1061         else if (!strncasecmp(cmdbuf,"OPNA",4)) {
1062                 cmd_opna(&cmdbuf[5]);
1063         }
1064
1065         else if (!strncasecmp(cmdbuf,"INFO",4)) {
1066                 cmd_info();
1067         }
1068
1069         else if (!strncasecmp(cmdbuf,"SLRP",4)) {
1070                 cmd_slrp(&cmdbuf[5]);
1071         }
1072
1073         else if (!strncasecmp(cmdbuf,"INVT",4)) {
1074                 cmd_invt_kick(&cmdbuf[5],1);
1075         }
1076
1077         else if (!strncasecmp(cmdbuf,"KICK",4)) {
1078                 cmd_invt_kick(&cmdbuf[5],0);
1079         }
1080
1081         else if (!strncasecmp(cmdbuf,"GETR",4)) {
1082                 cmd_getr();
1083         }
1084
1085         else if (!strncasecmp(cmdbuf,"SETR",4)) {
1086                 cmd_setr(&cmdbuf[5]);
1087         }
1088
1089         else if (!strncasecmp(cmdbuf,"GETA",4)) {
1090                 cmd_geta();
1091         }
1092
1093         else if (!strncasecmp(cmdbuf,"SETA",4)) {
1094                 cmd_seta(&cmdbuf[5]);
1095         }
1096
1097         else if (!strncasecmp(cmdbuf,"ENT0",4)) {
1098                 cmd_ent0(&cmdbuf[5]);
1099         }
1100
1101         else if (!strncasecmp(cmdbuf,"RINF",4)) {
1102                 cmd_rinf();
1103         }
1104
1105         else if (!strncasecmp(cmdbuf,"DELE",4)) {
1106                 cmd_dele(&cmdbuf[5]);
1107         }
1108
1109         else if (!strncasecmp(cmdbuf,"KILL",4)) {
1110                 cmd_kill(&cmdbuf[5]);
1111         }
1112
1113         else if (!strncasecmp(cmdbuf,"CRE8",4)) {
1114                 cmd_cre8(&cmdbuf[5]);
1115         }
1116
1117         else if (!strncasecmp(cmdbuf,"MOVE",4)) {
1118                 cmd_move(&cmdbuf[5]);
1119         }
1120
1121         else if (!strncasecmp(cmdbuf,"FORG",4)) {
1122                 cmd_forg();
1123         }
1124
1125         else if (!strncasecmp(cmdbuf,"MESG",4)) {
1126                 cmd_mesg(&cmdbuf[5]);
1127         }
1128
1129         else if (!strncasecmp(cmdbuf,"EMSG",4)) {
1130                 cmd_emsg(&cmdbuf[5]);
1131         }
1132
1133         else if (!strncasecmp(cmdbuf,"GNUR",4)) {
1134                 cmd_gnur();
1135         }
1136
1137         else if (!strncasecmp(cmdbuf,"VALI",4)) {
1138                 cmd_vali(&cmdbuf[5]);
1139         }
1140
1141         else if (!strncasecmp(cmdbuf,"EINF",4)) {
1142                 cmd_einf(&cmdbuf[5]);
1143         }
1144
1145         else if (!strncasecmp(cmdbuf,"LIST",4)) {
1146                 cmd_list();
1147         }
1148
1149         else if (!strncasecmp(cmdbuf,"CHEK",4)) {
1150                 cmd_chek();
1151         }
1152
1153         else if (!strncasecmp(cmdbuf,"DELF",4)) {
1154                 cmd_delf(&cmdbuf[5]);
1155         }
1156
1157         else if (!strncasecmp(cmdbuf,"MOVF",4)) {
1158                 cmd_movf(&cmdbuf[5]);
1159         }
1160
1161         else if (!strncasecmp(cmdbuf,"NETF",4)) {
1162                 cmd_netf(&cmdbuf[5]);
1163         }
1164
1165         else if (!strncasecmp(cmdbuf,"OPEN",4)) {
1166                 cmd_open(&cmdbuf[5]);
1167         }
1168
1169         else if (!strncasecmp(cmdbuf,"CLOS",4)) {
1170                 cmd_clos();
1171         }
1172
1173         else if (!strncasecmp(cmdbuf,"UOPN",4)) {
1174                 cmd_uopn(&cmdbuf[5]);
1175         }
1176
1177         else if (!strncasecmp(cmdbuf,"UCLS",4)) {
1178                 cmd_ucls(&cmdbuf[5]);
1179         }
1180
1181         else if (!strncasecmp(cmdbuf,"READ",4)) {
1182                 cmd_read(&cmdbuf[5]);
1183         }
1184
1185         else if (!strncasecmp(cmdbuf,"WRIT",4)) {
1186                 cmd_writ(&cmdbuf[5]);
1187         }
1188
1189         else if (!strncasecmp(cmdbuf,"QUSR",4)) {
1190                 cmd_qusr(&cmdbuf[5]);
1191         }
1192
1193         else if (!strncasecmp(cmdbuf,"ECHO",4)) {
1194                 cmd_echo(&cmdbuf[5]);
1195         }
1196
1197         else if (!strncasecmp(cmdbuf,"OIMG",4)) {
1198                 cmd_oimg(&cmdbuf[5]);
1199         }
1200
1201         else if (!strncasecmp(cmdbuf,"MORE",4)) {
1202                 cmd_more();
1203         }
1204
1205         else if (!strncasecmp(cmdbuf,"NDOP",4)) {
1206                 cmd_ndop(&cmdbuf[5]);
1207         }
1208
1209         else if (!strncasecmp(cmdbuf,"NUOP",4)) {
1210                 cmd_nuop(&cmdbuf[5]);
1211         }
1212
1213         else if (!strncasecmp(cmdbuf,"LFLR",4)) {
1214                 cmd_lflr();
1215         }
1216
1217         else if (!strncasecmp(cmdbuf,"CFLR",4)) {
1218                 cmd_cflr(&cmdbuf[5]);
1219         }
1220
1221         else if (!strncasecmp(cmdbuf,"KFLR",4)) {
1222                 cmd_kflr(&cmdbuf[5]);
1223         }
1224
1225         else if (!strncasecmp(cmdbuf,"EFLR",4)) {
1226                 cmd_eflr(&cmdbuf[5]);
1227         }
1228
1229         else if (!strncasecmp(cmdbuf,"IDEN",4)) {
1230                 cmd_iden(&cmdbuf[5]);
1231         }
1232
1233         else if (!strncasecmp(cmdbuf,"IPGM",4)) {
1234                 cmd_ipgm(&cmdbuf[5]);
1235         }
1236
1237         else if (!strncasecmp(cmdbuf,"TERM",4)) {
1238                 cmd_term(&cmdbuf[5]);
1239         }
1240
1241         else if (!strncasecmp(cmdbuf,"DOWN",4)) {
1242                 cmd_down();
1243         }
1244
1245         else if (!strncasecmp(cmdbuf,"SCDN",4)) {
1246                 cmd_scdn(&cmdbuf[5]);
1247         }
1248
1249         else if (!strncasecmp(cmdbuf, "UIMG", 4)) {
1250                 cmd_uimg(&cmdbuf[5]);
1251         }
1252
1253         else if (!strncasecmp(cmdbuf, "TIME", 4)) {
1254                 cmd_time();
1255         }
1256
1257         else if (!strncasecmp(cmdbuf, "AGUP", 4)) {
1258                 cmd_agup(&cmdbuf[5]);
1259         }
1260
1261         else if (!strncasecmp(cmdbuf, "ASUP", 4)) {
1262                 cmd_asup(&cmdbuf[5]);
1263         }
1264
1265         else if (!strncasecmp(cmdbuf, "GPEX", 4)) {
1266                 cmd_gpex(&cmdbuf[5]);
1267         }
1268
1269         else if (!strncasecmp(cmdbuf, "SPEX", 4)) {
1270                 cmd_spex(&cmdbuf[5]);
1271         }
1272
1273         else if (!strncasecmp(cmdbuf, "CONF", 4)) {
1274                 cmd_conf(&cmdbuf[5]);
1275         }
1276
1277         else if (!strncasecmp(cmdbuf, "SEEN", 4)) {
1278                 cmd_seen(&cmdbuf[5]);
1279         }
1280
1281         else if (!strncasecmp(cmdbuf, "GTSN", 4)) {
1282                 cmd_gtsn(&cmdbuf[5]);
1283         }
1284
1285         else if (!strncasecmp(cmdbuf, "VIEW", 4)) {
1286                 cmd_view(&cmdbuf[5]);
1287         }
1288
1289         else if (!strncasecmp(cmdbuf, "ISME", 4)) {
1290                 cmd_isme(&cmdbuf[5]);
1291         }
1292
1293 #ifdef DEBUG_MEMORY_LEAKS
1294         else if (!strncasecmp(cmdbuf, "LEAK", 4)) {
1295                 dump_tracked();
1296         }
1297 #endif
1298
1299         else if (!DLoader_Exec_Cmd(cmdbuf)) {
1300                 cprintf("%d Unrecognized or unsupported command.\n", ERROR);
1301                }
1302
1303         /* Run any after-each-command outines registered by modules */
1304         PerformSessionHooks(EVT_CMD);
1305 }