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, "");
 413                 /* FIXME add localhost */
 414                 /* FIXME add config.c_fqdn */
 415
 416                 fp = fopen("public_clients", "r");
 417                 if (fp != NULL) while (fgets(buf, sizeof buf, fp)!=NULL) {
 418                         while (isspace((buf[strlen(buf)-1]))) {
 419                                 buf[strlen(buf)-1] = 0;
 420                         }
 421                         if (hostname_to_dotted_quad(addrbuf, buf) == 0) {
 422                                 if ((strlen(public_clients) +
 423                                    strlen(addrbuf) + 2)
 424                                    < sizeof(public_clients)) {
 425                                         if (strlen(public_clients) != 0) {
 426                                                 strcat(public_clients, "|");
 427                                         }
 428                                         strcat(public_clients, addrbuf);
 429                                 }
 430                         }
 431                 }
 432                 fclose(fp);
 433                 pc_timestamp = time(NULL);
 434                 end_critical_section(S_PUBLIC_CLIENTS);
 435         }
 436
 437         lprintf(9, "Checking whether %s is a local or public client\n",
 438                 CC->cs_addr);
 439         for (i=0; i<num_parms(public_clients); ++i) {
 440                 extract(addrbuf, public_clients, i);
 441                 if (!strcasecmp(CC->cs_addr, addrbuf)) {
 442                         lprintf(9, "... yes it is.\n");
 443                         return(1);
 444                 }
 445         }
 446
 447         /* No hits.  This is not a public client. */
 448         lprintf(9, "... no it isn't.\n");
 449         return(0);
 450 }
 451
 452
 453 /*
 454  * the client is identifying itself to the server
 455  */
 456 void cmd_iden(char *argbuf)
 457 {
 458         int dev_code;
 459         int cli_code;
 460         int rev_level;
 461         char desc[SIZ];
 462         char from_host[SIZ];
 463         struct in_addr addr;
 464         int do_lookup = 0;
 465
 466         if (num_parms(argbuf)<4) {
 467                 cprintf("%d usage error\n",ERROR);
 468                 return;
 469         }
 470
 471         dev_code = extract_int(argbuf,0);
 472         cli_code = extract_int(argbuf,1);
 473         rev_level = extract_int(argbuf,2);
 474         extract(desc,argbuf,3);
 475
 476         safestrncpy(from_host, config.c_fqdn, sizeof from_host);
 477         from_host[sizeof from_host - 1] = 0;
 478         if (num_parms(argbuf)>=5) extract(from_host,argbuf,4);
 479
 480         CC->cs_clientdev = dev_code;
 481         CC->cs_clienttyp = cli_code;
 482         CC->cs_clientver = rev_level;
 483         safestrncpy(CC->cs_clientname, desc, sizeof CC->cs_clientname);
 484         CC->cs_clientname[31] = 0;
 485
 486         if (strlen(from_host) > 0) {
 487                 if (CC->is_local_socket) do_lookup = 1;
 488                 else if (is_public_client()) do_lookup = 1;
 489         }
 490
 491         if (do_lookup) {
 492                 lprintf(9, "Looking up hostname '%s'\n", from_host);
 493                 if ((addr.s_addr = inet_addr(from_host)) != -1) {
 494                         locate_host(CC->cs_host, sizeof CC->cs_host,
 495                                 NULL, 0,
 496                                 &addr);
 497                 }
 498                 else {
 499                         safestrncpy(CC->cs_host, from_host, sizeof CC->cs_host);
 500                         CC->cs_host[sizeof CC->cs_host - 1] = 0;
 501                 }
 502         }
 503
 504         lprintf(7, "client %d/%d/%01d.%02d (%s)\n",
 505                 dev_code,
 506                 cli_code,
 507                 (rev_level / 100),
 508                 (rev_level % 100),
 509                 desc);
 510
 511         syslog(LOG_NOTICE,"session %d: client %d/%d/%01d.%02d (%s) from %s\n",
 512                 CC->cs_pid,
 513                 dev_code,
 514                 cli_code,
 515                 (rev_level / 100),
 516                 (rev_level % 100),
 517                 desc,
 518                 CC->cs_host);
 519         cprintf("%d Ok\n",CIT_OK);
 520 }
 521
 522
 523 /*
 524  * display system messages or help
 525  */
 526 void cmd_mesg(char *mname)
 527 {
 528         FILE *mfp;
 529         char targ[SIZ];
 530         char buf[SIZ];
 531         char buf2[SIZ];
 532         char *dirs[2];
 533
 534         extract(buf,mname,0);
 535
 536         dirs[0]=mallok(64);
 537         dirs[1]=mallok(64);
 538         strcpy(dirs[0],"messages");
 539         strcpy(dirs[1],"help");
 540         snprintf(buf2, sizeof buf2, "%s.%d.%d", buf, CC->cs_clientdev, CC->cs_clienttyp);
 541         mesg_locate(targ,sizeof targ,buf2,2,(const char **)dirs);
 542         if (strlen(targ) == 0) {
 543                 snprintf(buf2, sizeof buf2, "%s.%d", buf, CC->cs_clientdev);
 544                 mesg_locate(targ,sizeof targ,buf2,2,(const char **)dirs);
 545                 if (strlen(targ) == 0) {
 546                         mesg_locate(targ,sizeof targ,buf,2,(const char **)dirs);
 547                 }
 548         }
 549         phree(dirs[0]);
 550         phree(dirs[1]);
 551
 552         if (strlen(targ)==0) {
 553                 cprintf("%d '%s' not found.\n",ERROR,mname);
 554                 return;
 555         }
 556
 557         mfp = fopen(targ,"r");
 558         if (mfp==NULL) {
 559                 cprintf("%d Cannot open '%s': %s\n",
 560                         ERROR,targ,strerror(errno));
 561                 return;
 562         }
 563         cprintf("%d %s\n",LISTING_FOLLOWS,buf);
 564
 565         while (fgets(buf, (SIZ-1), mfp)!=NULL) {
 566                 buf[strlen(buf)-1] = 0;
 567                 do_help_subst(buf);
 568                 cprintf("%s\n",buf);
 569         }
 570
 571         fclose(mfp);
 572         cprintf("000\n");
 573 }
 574
 575
 576 /*
 577  * enter system messages or help
 578  */
 579 void cmd_emsg(char *mname)
 580 {
 581         FILE *mfp;
 582         char targ[SIZ];
 583         char buf[SIZ];
 584         char *dirs[2];
 585         int a;
 586
 587         if (CtdlAccessCheck(ac_aide)) return;
 588
 589         extract(buf,mname,0);
 590         for (a=0; a<strlen(buf); ++a) {         /* security measure */
 591                 if (buf[a] == '/') buf[a] = '.';
 592         }
 593
 594         dirs[0]=mallok(64);
 595         dirs[1]=mallok(64);
 596         strcpy(dirs[0],"messages");
 597         strcpy(dirs[1],"help");
 598         mesg_locate(targ,sizeof targ,buf,2,(const char**)dirs);
 599         phree(dirs[0]);
 600         phree(dirs[1]);
 601
 602         if (strlen(targ)==0) {
 603                 snprintf(targ, sizeof targ, "./help/%s", buf);
 604         }
 605
 606         mfp = fopen(targ,"w");
 607         if (mfp==NULL) {
 608                 cprintf("%d Cannot open '%s': %s\n",
 609                         ERROR,targ,strerror(errno));
 610                 return;
 611         }
 612         cprintf("%d %s\n", SEND_LISTING, targ);
 613
 614         while (client_gets(buf), strcmp(buf, "000")) {
 615                 fprintf(mfp, "%s\n", buf);
 616         }
 617
 618         fclose(mfp);
 619 }
 620
 621
 622 /* Don't show the names of private rooms unless the viewing
 623  * user also knows the rooms.
 624  */
 625 void GenerateRoomDisplay(char *real_room,
 626                         struct CitContext *viewed,
 627                         struct CitContext *viewer) {
 628
 629         strcpy(real_room, viewed->room.QRname);
 630         if (viewed->room.QRflags & QR_MAILBOX) {
 631                 strcpy(real_room, &real_room[11]);
 632         }
 633         if (viewed->room.QRflags & QR_PRIVATE) {
 634                 if ( (CtdlRoomAccess(&viewed->room, &viewer->user)
 635                    & UA_KNOWN) == 0) {
 636                         strcpy(real_room, "<private room>");
 637                 }
 638         }
 639
 640         if (viewed->cs_flags & CS_CHAT) {
 641                 while (strlen(real_room) < 14)
 642                         strcat(real_room, " ");
 643
 644                 strcpy(&real_room[14], "<chat>");
 645         }
 646
 647 }
 648
 649 /*
 650  * Convenience function.
 651  */
 652 int CtdlAccessCheck(int required_level) {
 653
 654         if (CC->internal_pgm) return(0);
 655         if (required_level >= ac_internal) {
 656                 cprintf("%d This is not a user-level command.\n",
 657                         ERROR+HIGHER_ACCESS_REQUIRED);
 658                 return(-1);
 659         }
 660
 661         if (CC->user.axlevel >= 6) return(0);
 662         if (required_level >= ac_aide) {
 663                 cprintf("%d This command requires Aide access.\n",
 664                         ERROR+HIGHER_ACCESS_REQUIRED);
 665                 return(-1);
 666         }
 667
 668         if (is_room_aide()) return(0);
 669         if (required_level >= ac_room_aide) {
 670                 cprintf("%d This command requires Aide or Room Aide access.\n",
 671                         ERROR + HIGHER_ACCESS_REQUIRED);
 672                 return(-1);
 673         }
 674
 675         if (CC->logged_in) return(0);
 676         if (required_level >= ac_logged_in) {
 677                 cprintf("%d Not logged in.\n", ERROR+NOT_LOGGED_IN);
 678                 return(-1);
 679         }
 680
 681         /* shhh ... succeed quietly */
 682         return(0);
 683 }
 684
 685
 686
 687 /*
 688  * Terminate another running session
 689  */
 690 void cmd_term(char *cmdbuf)
 691 {
 692         int session_num;
 693         struct CitContext *ccptr;
 694         int found_it = 0;
 695         int allowed = 0;
 696
 697         session_num = extract_int(cmdbuf, 0);
 698         if (session_num == CC->cs_pid) {
 699                 cprintf("%d You can't kill your own session.\n", ERROR);
 700                 return;
 701         }
 702
 703         lprintf(9, "Locating session to kill\n");
 704         begin_critical_section(S_SESSION_TABLE);
 705         for (ccptr = ContextList; ccptr != NULL; ccptr = ccptr->next) {
 706                 if (session_num == ccptr->cs_pid) {
 707                         found_it = 1;
 708                         if ((ccptr->user.usernum == CC->user.usernum)
 709                            || (CC->user.axlevel >= 6)) {
 710                                 allowed = 1;
 711                                 ccptr->kill_me = 1;
 712                         }
 713                         else {
 714                                 allowed = 0;
 715                         }
 716                 }
 717         }
 718         end_critical_section(S_SESSION_TABLE);
 719
 720         if (found_it) {
 721                 if (allowed) {
 722                         cprintf("%d Session terminated.\n", CIT_OK);
 723                 }
 724                 else {
 725                         cprintf("%d You are not allowed to do that.\n",
 726                                 ERROR + HIGHER_ACCESS_REQUIRED);
 727                 }
 728         }
 729         else {
 730                 cprintf("%d No such session.\n", ERROR);
 731         }
 732 }
 733
 734
 735
 736
 737
 738 /*
 739  * get the paginator prompt
 740  */
 741 void cmd_more(void) {
 742         cprintf("%d %s\n", CIT_OK, config.c_moreprompt);
 743 }
 744
 745 /*
 746  * echo
 747  */
 748 void cmd_echo(char *etext)
 749 {
 750         cprintf("%d %s\n", CIT_OK, etext);
 751 }
 752
 753
 754
 755 /*
 756  * identify as internal program
 757  */
 758 void cmd_ipgm(char *argbuf)
 759 {
 760         int secret;
 761
 762         secret = extract_int(argbuf, 0);
 763         if (secret == config.c_ipgm_secret) {
 764                 CC->internal_pgm = 1;
 765                 strcpy(CC->curr_user, "<internal program>");
 766                 CC->cs_flags = CC->cs_flags|CS_STEALTH;
 767                 cprintf("%d Authenticated as an internal program.\n",CIT_OK);
 768         }
 769         else {
 770                 cprintf("%d Authentication failed.\n",ERROR);
 771                 lprintf(3, "Warning: ipgm authentication failed.\n");
 772         }
 773 }
 774
 775
 776 /*
 777  * Shut down the server
 778  */
 779 void cmd_down(void) {
 780
 781         if (CtdlAccessCheck(ac_aide)) return;
 782
 783         cprintf("%d Shutting down server.  Goodbye.\n", CIT_OK);
 784         time_to_die = 1;
 785 }
 786
 787 /*
 788  * Schedule or cancel a server shutdown
 789  */
 790 void cmd_scdn(char *argbuf)
 791 {
 792         int new_state;
 793
 794         if (CtdlAccessCheck(ac_aide)) return;
 795
 796         new_state = extract_int(argbuf, 0);
 797         if ((new_state == 0) || (new_state == 1)) {
 798                 ScheduledShutdown = new_state;
 799         }
 800         cprintf("%d %d\n", CIT_OK, ScheduledShutdown);
 801 }
 802
 803
 804 /*
 805  * Set or unset asynchronous protocol mode
 806  */
 807 void cmd_asyn(char *argbuf)
 808 {
 809         int new_state;
 810
 811         new_state = extract_int(argbuf, 0);
 812         if ((new_state == 0) || (new_state == 1)) {
 813                 CC->is_async = new_state;
 814         }
 815         cprintf("%d %d\n", CIT_OK, CC->is_async);
 816 }
 817
 818
 819 /*
 820  * Generate a "nonce" for APOP-style authentication.
 821  *
 822  * RFC 1725 et al specify a PID to be placed in front of the nonce.
 823  * Quoth BTX: That would be stupid.
 824  */
 825 void generate_nonce(struct CitContext *con) {
 826         struct timeval tv;
 827
 828         memset(con->cs_nonce, NONCE_SIZE, 0);
 829         gettimeofday(&tv, NULL);
 830         memset(con->cs_nonce, NONCE_SIZE, 0);
 831         snprintf(con->cs_nonce, NONCE_SIZE, "<%d%ld@%s>",
 832                 rand(), (long)tv.tv_usec, config.c_fqdn);
 833 }
 834
 835
 836
 837
 838 /*
 839  * Back-end function for starting a session
 840  */
 841 void begin_session(struct CitContext *con)
 842 {
 843         int len;        /* should be socklen_t but doesn't work on Macintosh */
 844         struct sockaddr_in sin;
 845
 846         /*
 847          * Initialize some variables specific to our context.
 848          */
 849         con->logged_in = 0;
 850         con->internal_pgm = 0;
 851         con->download_fp = NULL;
 852         con->upload_fp = NULL;
 853         con->FirstExpressMessage = NULL;
 854         time(&con->lastcmd);
 855         time(&con->lastidle);
 856         strcpy(con->lastcmdname, "    ");
 857         strcpy(con->cs_clientname, "(unknown)");
 858         strcpy(con->curr_user, NLI);
 859         strcpy(con->net_node,"");
 860         strcpy(con->fake_username, "");
 861         strcpy(con->fake_postname, "");
 862         strcpy(con->fake_hostname, "");
 863         strcpy(con->fake_roomname, "");
 864         generate_nonce(con);
 865         snprintf(con->temp, sizeof con->temp, tmpnam(NULL));
 866         safestrncpy(con->cs_host, config.c_fqdn, sizeof con->cs_host);
 867         safestrncpy(con->cs_addr, "", sizeof con->cs_addr);
 868         con->cs_host[sizeof con->cs_host - 1] = 0;
 869         len = sizeof sin;
 870         if (!CC->is_local_socket) {
 871                 if (!getpeername(con->client_socket,
 872                    (struct sockaddr *) &sin, &len))
 873                         locate_host(con->cs_host, sizeof con->cs_host,
 874                                 con->cs_addr, sizeof con->cs_addr,
 875                                 &sin.sin_addr);
 876         }
 877         else {
 878                 strcpy(con->cs_host, "");
 879         }
 880         con->cs_flags = 0;
 881         con->upload_type = UPL_FILE;
 882         con->dl_is_net = 0;
 883         con->FirstSessData = NULL;
 884
 885         con->nologin = 0;
 886         if ((config.c_maxsessions > 0)&&(num_sessions > config.c_maxsessions))
 887                 con->nologin = 1;
 888
 889         lprintf(3, "Session started.\n");
 890         syslog(LOG_NOTICE,"session %d: ended", con->cs_pid);
 891
 892         /* Run any session startup routines registered by loadable modules */
 893         PerformSessionHooks(EVT_START);
 894 }
 895
 896
 897 void citproto_begin_session() {
 898         if (CC->nologin==1) {
 899                 cprintf("%d %s: Too many users are already online "
 900                         "(maximum is %d)\n",
 901                         ERROR+MAX_SESSIONS_EXCEEDED,
 902                         config.c_nodename, config.c_maxsessions);
 903         }
 904         else {
 905                 cprintf("%d %s Citadel/UX server ready.\n",
 906                         CIT_OK, config.c_nodename);
 907         }
 908 }
 909
 910
 911
 912
 913 /*
 914  * This loop recognizes all server commands.
 915  */
 916 void do_command_loop(void) {
 917         char cmdbuf[SIZ];
 918
 919         time(&CC->lastcmd);
 920         memset(cmdbuf, 0, sizeof cmdbuf); /* Clear it, just in case */
 921         if (client_gets(cmdbuf) < 1) {
 922                 lprintf(3, "Client socket is broken.  Ending session.\n");
 923                 CC->kill_me = 1;
 924                 return;
 925         }
 926         lprintf(5, "Citadel: %s\n", cmdbuf);
 927
 928         /*
 929          * Let other clients see the last command we executed, and
 930          * update the idle time, but not NOOP, QNOP, PEXP, or GEXP.
 931          */
 932         if ( (strncasecmp(cmdbuf, "NOOP", 4))
 933            && (strncasecmp(cmdbuf, "QNOP", 4))
 934            && (strncasecmp(cmdbuf, "PEXP", 4))
 935            && (strncasecmp(cmdbuf, "GEXP", 4)) ) {
 936                 strcpy(CC->lastcmdname, "    ");
 937                 safestrncpy(CC->lastcmdname, cmdbuf,
 938                         sizeof(CC->lastcmdname) );
 939                 time(&CC->lastidle);
 940         }
 941
 942         if ((strncasecmp(cmdbuf, "ENT0", 4))
 943            && (strncasecmp(cmdbuf, "MESG", 4))
 944            && (strncasecmp(cmdbuf, "MSGS", 4)))
 945         {
 946            CC->cs_flags &= ~CS_POSTING;
 947         }
 948
 949         if (!strncasecmp(cmdbuf,"NOOP",4)) {
 950                 cprintf("%d%cok\n",CIT_OK,CtdlCheckExpress());
 951         }
 952
 953         else if (!strncasecmp(cmdbuf,"QNOP",4)) {
 954                 /* do nothing, this command returns no response */
 955         }
 956
 957         else if (!strncasecmp(cmdbuf,"QUIT",4)) {
 958                 cprintf("%d Goodbye.\n",CIT_OK);
 959                 CC->kill_me = 1;
 960         }
 961
 962         else if (!strncasecmp(cmdbuf,"ASYN",4)) {
 963                 cmd_asyn(&cmdbuf[5]);
 964         }
 965
 966         else if (!strncasecmp(cmdbuf,"LOUT",4)) {
 967                 if (CC->logged_in) logout(CC);
 968                 cprintf("%d logged out.\n",CIT_OK);
 969         }
 970
 971         else if (!strncasecmp(cmdbuf,"USER",4)) {
 972                 cmd_user(&cmdbuf[5]);
 973         }
 974
 975         else if (!strncasecmp(cmdbuf,"PASS",4)) {
 976                 cmd_pass(&cmdbuf[5]);
 977         }
 978
 979         else if (!strncasecmp(cmdbuf,"NEWU",4)) {
 980                 cmd_newu(&cmdbuf[5]);
 981         }
 982
 983         else if (!strncasecmp(cmdbuf,"CREU",4)) {
 984                 cmd_creu(&cmdbuf[5]);
 985         }
 986
 987         else if (!strncasecmp(cmdbuf,"SETP",4)) {
 988                 cmd_setp(&cmdbuf[5]);
 989         }
 990
 991         else if (!strncasecmp(cmdbuf,"LRMS",4)) {
 992                 cmd_lrms(&cmdbuf[5]);
 993         }
 994
 995         else if (!strncasecmp(cmdbuf,"LKRA",4)) {
 996                 cmd_lkra(&cmdbuf[5]);
 997         }
 998
 999         else if (!strncasecmp(cmdbuf,"LKRN",4)) {
1000                 cmd_lkrn(&cmdbuf[5]);
1001         }
1002
1003         else if (!strncasecmp(cmdbuf,"LKRO",4)) {
1004                 cmd_lkro(&cmdbuf[5]);
1005         }
1006
1007         else if (!strncasecmp(cmdbuf,"LZRM",4)) {
1008                 cmd_lzrm(&cmdbuf[5]);
1009         }
1010
1011         else if (!strncasecmp(cmdbuf,"LPRM",4)) {
1012                 cmd_lprm(&cmdbuf[5]);
1013         }
1014
1015         else if (!strncasecmp(cmdbuf,"GETU",4)) {
1016                 cmd_getu();
1017         }
1018
1019         else if (!strncasecmp(cmdbuf,"SETU",4)) {
1020                 cmd_setu(&cmdbuf[5]);
1021         }
1022
1023         else if (!strncasecmp(cmdbuf,"GOTO",4)) {
1024                 cmd_goto(&cmdbuf[5]);
1025         }
1026
1027         else if (!strncasecmp(cmdbuf,"MSGS",4)) {
1028                 cmd_msgs(&cmdbuf[5]);
1029         }
1030
1031         else if (!strncasecmp(cmdbuf,"WHOK",4)) {
1032                 cmd_whok();
1033         }
1034
1035         else if (!strncasecmp(cmdbuf,"RDIR",4)) {
1036                 cmd_rdir();
1037         }
1038
1039         else if (!strncasecmp(cmdbuf,"MSG0",4)) {
1040                 cmd_msg0(&cmdbuf[5]);
1041         }
1042
1043         else if (!strncasecmp(cmdbuf,"MSG2",4)) {
1044                 cmd_msg2(&cmdbuf[5]);
1045         }
1046
1047         else if (!strncasecmp(cmdbuf,"MSG3",4)) {
1048                 cmd_msg3(&cmdbuf[5]);
1049         }
1050
1051         else if (!strncasecmp(cmdbuf,"MSG4",4)) {
1052                 cmd_msg4(&cmdbuf[5]);
1053         }
1054
1055         else if (!strncasecmp(cmdbuf,"MSGP",4)) {
1056                 cmd_msgp(&cmdbuf[5]);
1057         }
1058
1059         else if (!strncasecmp(cmdbuf,"OPNA",4)) {
1060                 cmd_opna(&cmdbuf[5]);
1061         }
1062
1063         else if (!strncasecmp(cmdbuf,"INFO",4)) {
1064                 cmd_info();
1065         }
1066
1067         else if (!strncasecmp(cmdbuf,"SLRP",4)) {
1068                 cmd_slrp(&cmdbuf[5]);
1069         }
1070
1071         else if (!strncasecmp(cmdbuf,"INVT",4)) {
1072                 cmd_invt_kick(&cmdbuf[5],1);
1073         }
1074
1075         else if (!strncasecmp(cmdbuf,"KICK",4)) {
1076                 cmd_invt_kick(&cmdbuf[5],0);
1077         }
1078
1079         else if (!strncasecmp(cmdbuf,"GETR",4)) {
1080                 cmd_getr();
1081         }
1082
1083         else if (!strncasecmp(cmdbuf,"SETR",4)) {
1084                 cmd_setr(&cmdbuf[5]);
1085         }
1086
1087         else if (!strncasecmp(cmdbuf,"GETA",4)) {
1088                 cmd_geta();
1089         }
1090
1091         else if (!strncasecmp(cmdbuf,"SETA",4)) {
1092                 cmd_seta(&cmdbuf[5]);
1093         }
1094
1095         else if (!strncasecmp(cmdbuf,"ENT0",4)) {
1096                 cmd_ent0(&cmdbuf[5]);
1097         }
1098
1099         else if (!strncasecmp(cmdbuf,"RINF",4)) {
1100                 cmd_rinf();
1101         }
1102
1103         else if (!strncasecmp(cmdbuf,"DELE",4)) {
1104                 cmd_dele(&cmdbuf[5]);
1105         }
1106
1107         else if (!strncasecmp(cmdbuf,"KILL",4)) {
1108                 cmd_kill(&cmdbuf[5]);
1109         }
1110
1111         else if (!strncasecmp(cmdbuf,"CRE8",4)) {
1112                 cmd_cre8(&cmdbuf[5]);
1113         }
1114
1115         else if (!strncasecmp(cmdbuf,"MOVE",4)) {
1116                 cmd_move(&cmdbuf[5]);
1117         }
1118
1119         else if (!strncasecmp(cmdbuf,"FORG",4)) {
1120                 cmd_forg();
1121         }
1122
1123         else if (!strncasecmp(cmdbuf,"MESG",4)) {
1124                 cmd_mesg(&cmdbuf[5]);
1125         }
1126
1127         else if (!strncasecmp(cmdbuf,"EMSG",4)) {
1128                 cmd_emsg(&cmdbuf[5]);
1129         }
1130
1131         else if (!strncasecmp(cmdbuf,"GNUR",4)) {
1132                 cmd_gnur();
1133         }
1134
1135         else if (!strncasecmp(cmdbuf,"VALI",4)) {
1136                 cmd_vali(&cmdbuf[5]);
1137         }
1138
1139         else if (!strncasecmp(cmdbuf,"EINF",4)) {
1140                 cmd_einf(&cmdbuf[5]);
1141         }
1142
1143         else if (!strncasecmp(cmdbuf,"LIST",4)) {
1144                 cmd_list();
1145         }
1146
1147         else if (!strncasecmp(cmdbuf,"CHEK",4)) {
1148                 cmd_chek();
1149         }
1150
1151         else if (!strncasecmp(cmdbuf,"DELF",4)) {
1152                 cmd_delf(&cmdbuf[5]);
1153         }
1154
1155         else if (!strncasecmp(cmdbuf,"MOVF",4)) {
1156                 cmd_movf(&cmdbuf[5]);
1157         }
1158
1159         else if (!strncasecmp(cmdbuf,"NETF",4)) {
1160                 cmd_netf(&cmdbuf[5]);
1161         }
1162
1163         else if (!strncasecmp(cmdbuf,"OPEN",4)) {
1164                 cmd_open(&cmdbuf[5]);
1165         }
1166
1167         else if (!strncasecmp(cmdbuf,"CLOS",4)) {
1168                 cmd_clos();
1169         }
1170
1171         else if (!strncasecmp(cmdbuf,"UOPN",4)) {
1172                 cmd_uopn(&cmdbuf[5]);
1173         }
1174
1175         else if (!strncasecmp(cmdbuf,"UCLS",4)) {
1176                 cmd_ucls(&cmdbuf[5]);
1177         }
1178
1179         else if (!strncasecmp(cmdbuf,"READ",4)) {
1180                 cmd_read(&cmdbuf[5]);
1181         }
1182
1183         else if (!strncasecmp(cmdbuf,"WRIT",4)) {
1184                 cmd_writ(&cmdbuf[5]);
1185         }
1186
1187         else if (!strncasecmp(cmdbuf,"QUSR",4)) {
1188                 cmd_qusr(&cmdbuf[5]);
1189         }
1190
1191         else if (!strncasecmp(cmdbuf,"ECHO",4)) {
1192                 cmd_echo(&cmdbuf[5]);
1193         }
1194
1195         else if (!strncasecmp(cmdbuf,"OIMG",4)) {
1196                 cmd_oimg(&cmdbuf[5]);
1197         }
1198
1199         else if (!strncasecmp(cmdbuf,"MORE",4)) {
1200                 cmd_more();
1201         }
1202
1203         else if (!strncasecmp(cmdbuf,"NDOP",4)) {
1204                 cmd_ndop(&cmdbuf[5]);
1205         }
1206
1207         else if (!strncasecmp(cmdbuf,"NUOP",4)) {
1208                 cmd_nuop(&cmdbuf[5]);
1209         }
1210
1211         else if (!strncasecmp(cmdbuf,"LFLR",4)) {
1212                 cmd_lflr();
1213         }
1214
1215         else if (!strncasecmp(cmdbuf,"CFLR",4)) {
1216                 cmd_cflr(&cmdbuf[5]);
1217         }
1218
1219         else if (!strncasecmp(cmdbuf,"KFLR",4)) {
1220                 cmd_kflr(&cmdbuf[5]);
1221         }
1222
1223         else if (!strncasecmp(cmdbuf,"EFLR",4)) {
1224                 cmd_eflr(&cmdbuf[5]);
1225         }
1226
1227         else if (!strncasecmp(cmdbuf,"IDEN",4)) {
1228                 cmd_iden(&cmdbuf[5]);
1229         }
1230
1231         else if (!strncasecmp(cmdbuf,"IPGM",4)) {
1232                 cmd_ipgm(&cmdbuf[5]);
1233         }
1234
1235         else if (!strncasecmp(cmdbuf,"TERM",4)) {
1236                 cmd_term(&cmdbuf[5]);
1237         }
1238
1239         else if (!strncasecmp(cmdbuf,"DOWN",4)) {
1240                 cmd_down();
1241         }
1242
1243         else if (!strncasecmp(cmdbuf,"SCDN",4)) {
1244                 cmd_scdn(&cmdbuf[5]);
1245         }
1246
1247         else if (!strncasecmp(cmdbuf, "UIMG", 4)) {
1248                 cmd_uimg(&cmdbuf[5]);
1249         }
1250
1251         else if (!strncasecmp(cmdbuf, "TIME", 4)) {
1252                 cmd_time();
1253         }
1254
1255         else if (!strncasecmp(cmdbuf, "AGUP", 4)) {
1256                 cmd_agup(&cmdbuf[5]);
1257         }
1258
1259         else if (!strncasecmp(cmdbuf, "ASUP", 4)) {
1260                 cmd_asup(&cmdbuf[5]);
1261         }
1262
1263         else if (!strncasecmp(cmdbuf, "GPEX", 4)) {
1264                 cmd_gpex(&cmdbuf[5]);
1265         }
1266
1267         else if (!strncasecmp(cmdbuf, "SPEX", 4)) {
1268                 cmd_spex(&cmdbuf[5]);
1269         }
1270
1271         else if (!strncasecmp(cmdbuf, "CONF", 4)) {
1272                 cmd_conf(&cmdbuf[5]);
1273         }
1274
1275         else if (!strncasecmp(cmdbuf, "SEEN", 4)) {
1276                 cmd_seen(&cmdbuf[5]);
1277         }
1278
1279         else if (!strncasecmp(cmdbuf, "GTSN", 4)) {
1280                 cmd_gtsn(&cmdbuf[5]);
1281         }
1282
1283         else if (!strncasecmp(cmdbuf, "VIEW", 4)) {
1284                 cmd_view(&cmdbuf[5]);
1285         }
1286
1287         else if (!strncasecmp(cmdbuf, "ISME", 4)) {
1288                 cmd_isme(&cmdbuf[5]);
1289         }
1290
1291 #ifdef DEBUG_MEMORY_LEAKS
1292         else if (!strncasecmp(cmdbuf, "LEAK", 4)) {
1293                 dump_tracked();
1294         }
1295 #endif
1296
1297         else if (!DLoader_Exec_Cmd(cmdbuf)) {
1298                 cprintf("%d Unrecognized or unsupported command.\n", ERROR);
1299                }
1300
1301         /* Run any after-each-command outines registered by modules */
1302         PerformSessionHooks(EVT_CMD);
1303 }