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 <dlfcn.h> */
  38 #include <netdb.h>
  39 #include <sys/types.h>
  40 #include <sys/socket.h>
  41 #include <netinet/in.h>
  42 #include <arpa/inet.h>
  43 #include "citadel.h"
  44 #include "server.h"
  45 #include "serv_extensions.h"
  46 #include "sysdep_decls.h"
  47 #include "citserver.h"
  48 #include "config.h"
  49 #include "database.h"
  50 #include "housekeeping.h"
  51 #include "user_ops.h"
  52 #include "msgbase.h"
  53 #include "support.h"
  54 #include "locate_host.h"
  55 #include "room_ops.h"
  56 #include "file_ops.h"
  57 #include "policy.h"
  58 #include "control.h"
  59 #include "tools.h"
  60
  61 #ifndef HAVE_SNPRINTF
  62 #include "snprintf.h"
  63 #endif
  64
  65 struct CitContext *ContextList = NULL;
  66 char *unique_session_numbers;
  67 int ScheduledShutdown = 0;
  68 int do_defrag = 0;
  69 time_t server_startup_time;
  70
  71 /*
  72  * Various things that need to be initialized at startup
  73  */
  74 void master_startup(void) {
  75         struct timeval tv;
  76         unsigned int seed;
  77         FILE *urandom;
  78         struct ctdlroom qrbuf;
  79
  80         lprintf(9, "master_startup() started\n");
  81         time(&server_startup_time);
  82
  83         lprintf(7, "Opening databases\n");
  84         open_databases();
  85
  86         if (do_defrag) {
  87                 defrag_databases();
  88         }
  89
  90         check_ref_counts();
  91
  92         lprintf(7, "Creating base rooms (if necessary)\n");
  93         create_room(BASEROOM,           0, "", 0, 1, 0);
  94         create_room(AIDEROOM,           3, "", 0, 1, 0);
  95         create_room(SYSCONFIGROOM,      3, "", 0, 1, 0);
  96         create_room(config.c_twitroom,  0, "", 0, 1, 0);
  97
  98         /* The "Local System Configuration" room doesn't need to be visible */
  99         if (lgetroom(&qrbuf, SYSCONFIGROOM) == 0) {
 100                 qrbuf.QRflags2 |= QR2_SYSTEM;
 101                 lputroom(&qrbuf);
 102         }
 103
 104         lprintf(7, "Seeding the pseudo-random number generator...\n");
 105         urandom = fopen("/dev/urandom", "r");
 106         if (urandom != NULL) {
 107                 fread(&seed, sizeof seed, 1, urandom);
 108                 fclose(urandom);
 109         }
 110         else {
 111                 gettimeofday(&tv, NULL);
 112                 seed = tv.tv_usec;
 113         }
 114         srandom(seed);
 115
 116         lprintf(7, "Initializing ipgm secret\n");
 117         get_config();
 118         config.c_ipgm_secret = rand();
 119         put_config();
 120
 121         lprintf(9, "master_startup() finished\n");
 122 }
 123
 124
 125 /*
 126  * Cleanup routine to be called when the server is shutting down.
 127  * WARNING: It's no longer safe to call this function to force a shutdown.
 128  * Instead, set time_to_die = 1.
 129  */
 130 void master_cleanup(void) {
 131         struct CleanupFunctionHook *fcn;
 132
 133         /* Run any cleanup routines registered by loadable modules */
 134         for (fcn = CleanupHookTable; fcn != NULL; fcn = fcn->next) {
 135                 (*fcn->h_function_pointer)();
 136         }
 137
 138         /* Close databases */
 139         lprintf(7, "Closing databases\n");
 140         close_databases();
 141
 142         /* Do system-dependent stuff */
 143         sysdep_master_cleanup();
 144
 145         /* Now go away. */
 146         lprintf(3, "citserver: exiting.\n");
 147         fflush(stdout); fflush(stderr);
 148         exit(0);
 149 }
 150
 151
 152 /*
 153  * Free any per-session data allocated by modules or whatever
 154  */
 155 void deallocate_user_data(struct CitContext *con)
 156 {
 157         struct CtdlSessData *ptr;
 158
 159         begin_critical_section(S_SESSION_TABLE);
 160         while (con->FirstSessData != NULL) {
 161                 lprintf(9, "Deallocating user data symbol %ld\n",
 162                         con->FirstSessData->sym_id);
 163                 if (con->FirstSessData->sym_data != NULL)
 164                         phree(con->FirstSessData->sym_data);
 165                 ptr = con->FirstSessData->next;
 166                 phree(con->FirstSessData);
 167                 con->FirstSessData = ptr;
 168         }
 169         end_critical_section(S_SESSION_TABLE);
 170 }
 171
 172
 173
 174
 175 /*
 176  * Terminate a session and remove its context data structure.
 177  */
 178 void RemoveContext (struct CitContext *con)
 179 {
 180         struct CitContext *ptr = NULL;
 181         struct CitContext *ToFree = NULL;
 182
 183         if (con==NULL) {
 184                 lprintf(5, "WARNING: RemoveContext() called with NULL!\n");
 185                 return;
 186         }
 187         lprintf(9, "RemoveContext() called\n");
 188
 189         /* Remove the context from the global context list.  This needs
 190          * to get done FIRST to avoid concurrency problems.  It is *vitally*
 191          * important to keep num_sessions accurate!!
 192          */
 193         lprintf(7, "Removing context for session %d\n", con->cs_pid);
 194         begin_critical_section(S_SESSION_TABLE);
 195         if (ContextList == con) {
 196                 ToFree = ContextList;
 197                 ContextList = ContextList->next;
 198                 --num_sessions;
 199         }
 200         else {
 201                 for (ptr = ContextList; ptr != NULL; ptr = ptr->next) {
 202                         if (ptr->next == con) {
 203                                 ToFree = ptr->next;
 204                                 ptr->next = ptr->next->next;
 205                                 --num_sessions;
 206                         }
 207                 }
 208         }
 209         end_critical_section(S_SESSION_TABLE);
 210
 211         if (ToFree == NULL) {
 212                 lprintf(9, "RemoveContext() found nothing to remove\n");
 213                 return;
 214         }
 215
 216         /* Run any cleanup routines registered by loadable modules.
 217          * Note 1: This must occur *before* deallocate_user_data() because the
 218          *         cleanup functions might touch dynamic session data.
 219          * Note 2: We have to "become_session()" because the cleanup functions
 220          *         might make references to "CC" assuming it's the right one.
 221          */
 222         become_session(con);
 223         PerformSessionHooks(EVT_STOP);
 224         become_session(NULL);
 225
 226         /* Now handle all of the administrivia. */
 227         lprintf(7, "Calling logout(%d)\n", con->cs_pid);
 228         logout(con);
 229
 230         unlink(con->temp);
 231         lprintf(3, "Session %d: ended.\n", con->cs_pid);
 232
 233         /* Deallocate any user-data attached to this session */
 234         deallocate_user_data(con);
 235
 236         /* If the client is still connected, blow 'em away. */
 237         lprintf(7, "Closing socket %d\n", con->client_socket);
 238         close(con->client_socket);
 239
 240         /* This is where we used to check for scheduled shutdowns. */
 241
 242         /* Free up the memory used by this context */
 243         phree(con);
 244
 245         lprintf(9, "Done with RemoveContext()\n");
 246 }
 247
 248
 249
 250
 251
 252 /*
 253  * Return a pointer to some generic per-session user data.
 254  * (This function returns NULL if the requested symbol is not allocated.)
 255  *
 256  * NOTE: we use critical sections for allocating and de-allocating these,
 257  *       but not for locating one.
 258  */
 259 void *CtdlGetUserData(unsigned long requested_sym)
 260 {
 261         struct CtdlSessData *ptr;
 262
 263         for (ptr = CC->FirstSessData; ptr != NULL; ptr = ptr->next)
 264                 if (ptr->sym_id == requested_sym)
 265                         return(ptr->sym_data);
 266
 267         lprintf(2, "ERROR! CtdlGetUserData(%ld) symbol not allocated\n",
 268                 requested_sym);
 269         return NULL;
 270 }
 271
 272
 273 /*
 274  * Allocate some generic per-session user data.
 275  */
 276 void CtdlAllocUserData(unsigned long requested_sym, size_t num_bytes)
 277 {
 278         struct CtdlSessData *ptr;
 279
 280         lprintf(9, "CtdlAllocUserData(%ld) called\n", requested_sym);
 281
 282         /* Fail silently if the symbol is already registered. */
 283         for (ptr = CC->FirstSessData; ptr != NULL; ptr = ptr->next)  {
 284                 if (ptr->sym_id == requested_sym) {
 285                         return;
 286                 }
 287         }
 288
 289         /* Grab us some memory!  Dem's good eatin' !!  */
 290         ptr = mallok(sizeof(struct CtdlSessData));
 291         ptr->sym_id = requested_sym;
 292         ptr->sym_data = mallok(num_bytes);
 293         memset(ptr->sym_data, 0, num_bytes);
 294
 295         begin_critical_section(S_SESSION_TABLE);
 296         ptr->next = CC->FirstSessData;
 297         CC->FirstSessData = ptr;
 298         end_critical_section(S_SESSION_TABLE);
 299
 300         lprintf(9, "CtdlAllocUserData(%ld) finished\n", requested_sym);
 301 }
 302
 303
 304 /*
 305  * Change the size of a buffer allocated with CtdlAllocUserData()
 306  */
 307 void CtdlReallocUserData(unsigned long requested_sym, size_t num_bytes)
 308 {
 309         struct CtdlSessData *ptr;
 310
 311         for (ptr = CC->FirstSessData; ptr != NULL; ptr = ptr->next)  {
 312                 if (ptr->sym_id == requested_sym) {
 313                         ptr->sym_data = reallok(ptr->sym_data, num_bytes);
 314                         return;
 315                 }
 316         }
 317
 318         lprintf(2, "CtdlReallocUserData() ERROR: symbol %ld not found!\n",
 319                 requested_sym);
 320 }
 321
 322
 323
 324
 325
 326
 327 /*
 328  * cmd_info()  -  tell the client about this server
 329  */
 330 void cmd_info(void) {
 331         cprintf("%d Server info:\n", LISTING_FOLLOWS);
 332         cprintf("%d\n", CC->cs_pid);
 333         cprintf("%s\n", config.c_nodename);
 334         cprintf("%s\n", config.c_humannode);
 335         cprintf("%s\n", config.c_fqdn);
 336         cprintf("%s\n", CITADEL);
 337         cprintf("%d\n", REV_LEVEL);
 338         cprintf("%s\n", config.c_bbs_city);
 339         cprintf("%s\n", config.c_sysadm);
 340         cprintf("%d\n", SERVER_TYPE);
 341         cprintf("%s\n", config.c_moreprompt);
 342         cprintf("1\n"); /* 1 = yes, this system supports floors */
 343         cprintf("1\n"); /* 1 = we support the extended paging options */
 344         cprintf("%s\n", CC->cs_nonce);
 345         cprintf("1\n"); /* 1 = yes, this system supports the QNOP command */
 346         cprintf("000\n");
 347 }
 348
 349
 350 /*
 351  * returns an asterisk if there are any express messages waiting,
 352  * space otherwise.
 353  */
 354 char CtdlCheckExpress(void) {
 355         if (CC->FirstExpressMessage == NULL) {
 356                 return(' ');
 357         }
 358         else {
 359                 return('*');
 360         }
 361 }
 362
 363 void cmd_time(void)
 364 {
 365    time_t tv;
 366    struct tm *tmp;
 367
 368    tv = time(NULL);
 369    tmp = localtime(&tv);
 370
 371    /* timezone and daylight global variables are not portable. */
 372 #ifdef HAVE_STRUCT_TM_TM_GMTOFF
 373    cprintf("%d %ld|%ld|%d\n", CIT_OK, (long)tv, tmp->tm_gmtoff, tmp->tm_isdst);
 374 #else
 375    cprintf("%d %ld|%ld|%d\n", CIT_OK, (long)tv, timezone, tmp->tm_isdst);
 376 #endif
 377 }
 378
 379
 380 /*
 381  * Check originating host against the public_clients file.  This determines
 382  * whether the client is allowed to change the hostname for this session
 383  * (for example, to show the location of the user rather than the location
 384  * of the client).
 385  */
 386 int is_public_client(void)
 387 {
 388         char buf[SIZ];
 389         char addrbuf[SIZ];
 390         FILE *fp;
 391         int i;
 392         struct stat statbuf;
 393         static time_t pc_timestamp = 0;
 394         static char public_clients[SIZ];
 395
 396 #define PUBLIC_CLIENTS "./public_clients"
 397
 398         /*
 399          * Check the time stamp on the public_clients file.  If it's been
 400          * updated since the last time we were here (or if this is the first
 401          * time we've been through the loop), read its contents and learn
 402          * the IP addresses of the listed hosts.
 403          */
 404         if (stat(PUBLIC_CLIENTS, &statbuf) != 0) {
 405                 /* No public_clients file exists, so bail out */
 406                 lprintf(5, "Warning: '%s' does not exist\n", PUBLIC_CLIENTS);
 407                 return(0);
 408         }
 409
 410         if (statbuf.st_mtime > pc_timestamp) {
 411                 begin_critical_section(S_PUBLIC_CLIENTS);
 412                 lprintf(7, "Loading %s\n", PUBLIC_CLIENTS);
 413
 414                 strcpy(public_clients, "127.0.0.1");
 415                 if (hostname_to_dotted_quad(addrbuf, config.c_fqdn) == 0) {
 416                         strcat(public_clients, "|");
 417                         strcat(public_clients, addrbuf);
 418                 }
 419
 420                 fp = fopen("public_clients", "r");
 421                 if (fp != NULL) while (fgets(buf, sizeof buf, fp)!=NULL) {
 422                         for (i=0; i<strlen(buf); ++i) {
 423                                 if (buf[i] == '#') buf[i] = 0;
 424                         }
 425                         while (isspace((buf[strlen(buf)-1]))) {
 426                                 buf[strlen(buf)-1] = 0;
 427                         }
 428                         if (hostname_to_dotted_quad(addrbuf, buf) == 0) {
 429                                 if ((strlen(public_clients) +
 430                                    strlen(addrbuf) + 2)
 431                                    < sizeof(public_clients)) {
 432                                         strcat(public_clients, addrbuf);
 433                                 }
 434                         }
 435                 }
 436                 fclose(fp);
 437                 pc_timestamp = time(NULL);
 438                 end_critical_section(S_PUBLIC_CLIENTS);
 439         }
 440
 441         lprintf(9, "Checking whether %s is a local or public client\n",
 442                 CC->cs_addr);
 443         for (i=0; i<num_parms(public_clients); ++i) {
 444                 extract(addrbuf, public_clients, i);
 445                 if (!strcasecmp(CC->cs_addr, addrbuf)) {
 446                         lprintf(9, "... yes it is.\n");
 447                         return(1);
 448                 }
 449         }
 450
 451         /* No hits.  This is not a public client. */
 452         lprintf(9, "... no it isn't.\n");
 453         return(0);
 454 }
 455
 456
 457 /*
 458  * the client is identifying itself to the server
 459  */
 460 void cmd_iden(char *argbuf)
 461 {
 462         int dev_code;
 463         int cli_code;
 464         int rev_level;
 465         char desc[SIZ];
 466         char from_host[SIZ];
 467         struct in_addr addr;
 468         int do_lookup = 0;
 469
 470         if (num_parms(argbuf)<4) {
 471                 cprintf("%d usage error\n",ERROR);
 472                 return;
 473         }
 474
 475         dev_code = extract_int(argbuf,0);
 476         cli_code = extract_int(argbuf,1);
 477         rev_level = extract_int(argbuf,2);
 478         extract(desc,argbuf,3);
 479
 480         safestrncpy(from_host, config.c_fqdn, sizeof from_host);
 481         from_host[sizeof from_host - 1] = 0;
 482         if (num_parms(argbuf)>=5) extract(from_host,argbuf,4);
 483
 484         CC->cs_clientdev = dev_code;
 485         CC->cs_clienttyp = cli_code;
 486         CC->cs_clientver = rev_level;
 487         safestrncpy(CC->cs_clientname, desc, sizeof CC->cs_clientname);
 488         CC->cs_clientname[31] = 0;
 489
 490         if (strlen(from_host) > 0) {
 491                 if (CC->is_local_socket) do_lookup = 1;
 492                 else if (is_public_client()) do_lookup = 1;
 493         }
 494
 495         if (do_lookup) {
 496                 lprintf(9, "Looking up hostname '%s'\n", from_host);
 497                 if ((addr.s_addr = inet_addr(from_host)) != -1) {
 498                         locate_host(CC->cs_host, sizeof CC->cs_host,
 499                                 NULL, 0,
 500                                 &addr);
 501                 }
 502                 else {
 503                         safestrncpy(CC->cs_host, from_host, sizeof CC->cs_host);
 504                         CC->cs_host[sizeof CC->cs_host - 1] = 0;
 505                 }
 506         }
 507
 508         lprintf(3,"Session %d: Client %d/%d/%01d.%02d (%s) from %s\n",
 509                 CC->cs_pid,
 510                 dev_code,
 511                 cli_code,
 512                 (rev_level / 100),
 513                 (rev_level % 100),
 514                 desc,
 515                 CC->cs_host);
 516         cprintf("%d Ok\n",CIT_OK);
 517 }
 518
 519
 520 /*
 521  * display system messages or help
 522  */
 523 void cmd_mesg(char *mname)
 524 {
 525         FILE *mfp;
 526         char targ[SIZ];
 527         char buf[SIZ];
 528         char buf2[SIZ];
 529         char *dirs[2];
 530
 531         extract(buf,mname,0);
 532
 533         dirs[0]=mallok(64);
 534         dirs[1]=mallok(64);
 535         strcpy(dirs[0],"messages");
 536         strcpy(dirs[1],"help");
 537         snprintf(buf2, sizeof buf2, "%s.%d.%d", buf, CC->cs_clientdev, CC->cs_clienttyp);
 538         mesg_locate(targ,sizeof targ,buf2,2,(const char **)dirs);
 539         if (strlen(targ) == 0) {
 540                 snprintf(buf2, sizeof buf2, "%s.%d", buf, CC->cs_clientdev);
 541                 mesg_locate(targ,sizeof targ,buf2,2,(const char **)dirs);
 542                 if (strlen(targ) == 0) {
 543                         mesg_locate(targ,sizeof targ,buf,2,(const char **)dirs);
 544                 }
 545         }
 546         phree(dirs[0]);
 547         phree(dirs[1]);
 548
 549         if (strlen(targ)==0) {
 550                 cprintf("%d '%s' not found.\n",ERROR,mname);
 551                 return;
 552         }
 553
 554         mfp = fopen(targ,"r");
 555         if (mfp==NULL) {
 556                 cprintf("%d Cannot open '%s': %s\n",
 557                         ERROR,targ,strerror(errno));
 558                 return;
 559         }
 560         cprintf("%d %s\n",LISTING_FOLLOWS,buf);
 561
 562         while (fgets(buf, (SIZ-1), mfp)!=NULL) {
 563                 buf[strlen(buf)-1] = 0;
 564                 do_help_subst(buf);
 565                 cprintf("%s\n",buf);
 566         }
 567
 568         fclose(mfp);
 569         cprintf("000\n");
 570 }
 571
 572
 573 /*
 574  * enter system messages or help
 575  */
 576 void cmd_emsg(char *mname)
 577 {
 578         FILE *mfp;
 579         char targ[SIZ];
 580         char buf[SIZ];
 581         char *dirs[2];
 582         int a;
 583
 584         if (CtdlAccessCheck(ac_aide)) return;
 585
 586         extract(buf,mname,0);
 587         for (a=0; a<strlen(buf); ++a) {         /* security measure */
 588                 if (buf[a] == '/') buf[a] = '.';
 589         }
 590
 591         dirs[0]=mallok(64);
 592         dirs[1]=mallok(64);
 593         strcpy(dirs[0],"messages");
 594         strcpy(dirs[1],"help");
 595         mesg_locate(targ,sizeof targ,buf,2,(const char**)dirs);
 596         phree(dirs[0]);
 597         phree(dirs[1]);
 598
 599         if (strlen(targ)==0) {
 600                 snprintf(targ, sizeof targ, "./help/%s", buf);
 601         }
 602
 603         mfp = fopen(targ,"w");
 604         if (mfp==NULL) {
 605                 cprintf("%d Cannot open '%s': %s\n",
 606                         ERROR,targ,strerror(errno));
 607                 return;
 608         }
 609         cprintf("%d %s\n", SEND_LISTING, targ);
 610
 611         while (client_gets(buf), strcmp(buf, "000")) {
 612                 fprintf(mfp, "%s\n", buf);
 613         }
 614
 615         fclose(mfp);
 616 }
 617
 618
 619 /* Don't show the names of private rooms unless the viewing
 620  * user also knows the rooms.
 621  */
 622 void GenerateRoomDisplay(char *real_room,
 623                         struct CitContext *viewed,
 624                         struct CitContext *viewer) {
 625
 626         strcpy(real_room, viewed->room.QRname);
 627         if (viewed->room.QRflags & QR_MAILBOX) {
 628                 strcpy(real_room, &real_room[11]);
 629         }
 630         if (viewed->room.QRflags & QR_PRIVATE) {
 631                 if ( (CtdlRoomAccess(&viewed->room, &viewer->user)
 632                    & UA_KNOWN) == 0) {
 633                         strcpy(real_room, "<private room>");
 634                 }
 635         }
 636
 637         if (viewed->cs_flags & CS_CHAT) {
 638                 while (strlen(real_room) < 14)
 639                         strcat(real_room, " ");
 640
 641                 strcpy(&real_room[14], "<chat>");
 642         }
 643
 644 }
 645
 646 /*
 647  * Convenience function.
 648  */
 649 int CtdlAccessCheck(int required_level) {
 650
 651         if (CC->internal_pgm) return(0);
 652         if (required_level >= ac_internal) {
 653                 cprintf("%d This is not a user-level command.\n",
 654                         ERROR+HIGHER_ACCESS_REQUIRED);
 655                 return(-1);
 656         }
 657
 658         if (CC->user.axlevel >= 6) return(0);
 659         if (required_level >= ac_aide) {
 660                 cprintf("%d This command requires Aide access.\n",
 661                         ERROR+HIGHER_ACCESS_REQUIRED);
 662                 return(-1);
 663         }
 664
 665         if (is_room_aide()) return(0);
 666         if (required_level >= ac_room_aide) {
 667                 cprintf("%d This command requires Aide or Room Aide access.\n",
 668                         ERROR + HIGHER_ACCESS_REQUIRED);
 669                 return(-1);
 670         }
 671
 672         if (CC->logged_in) return(0);
 673         if (required_level >= ac_logged_in) {
 674                 cprintf("%d Not logged in.\n", ERROR+NOT_LOGGED_IN);
 675                 return(-1);
 676         }
 677
 678         /* shhh ... succeed quietly */
 679         return(0);
 680 }
 681
 682
 683
 684 /*
 685  * Terminate another running session
 686  */
 687 void cmd_term(char *cmdbuf)
 688 {
 689         int session_num;
 690         struct CitContext *ccptr;
 691         int found_it = 0;
 692         int allowed = 0;
 693
 694         session_num = extract_int(cmdbuf, 0);
 695         if (session_num == CC->cs_pid) {
 696                 cprintf("%d You can't kill your own session.\n", ERROR);
 697                 return;
 698         }
 699
 700         lprintf(9, "Locating session to kill\n");
 701         begin_critical_section(S_SESSION_TABLE);
 702         for (ccptr = ContextList; ccptr != NULL; ccptr = ccptr->next) {
 703                 if (session_num == ccptr->cs_pid) {
 704                         found_it = 1;
 705                         if ((ccptr->user.usernum == CC->user.usernum)
 706                            || (CC->user.axlevel >= 6)) {
 707                                 allowed = 1;
 708                                 ccptr->kill_me = 1;
 709                         }
 710                         else {
 711                                 allowed = 0;
 712                         }
 713                 }
 714         }
 715         end_critical_section(S_SESSION_TABLE);
 716
 717         if (found_it) {
 718                 if (allowed) {
 719                         cprintf("%d Session terminated.\n", CIT_OK);
 720                 }
 721                 else {
 722                         cprintf("%d You are not allowed to do that.\n",
 723                                 ERROR + HIGHER_ACCESS_REQUIRED);
 724                 }
 725         }
 726         else {
 727                 cprintf("%d No such session.\n", ERROR);
 728         }
 729 }
 730
 731
 732
 733
 734
 735 /*
 736  * get the paginator prompt
 737  */
 738 void cmd_more(void) {
 739         cprintf("%d %s\n", CIT_OK, config.c_moreprompt);
 740 }
 741
 742 /*
 743  * echo
 744  */
 745 void cmd_echo(char *etext)
 746 {
 747         cprintf("%d %s\n", CIT_OK, etext);
 748 }
 749
 750
 751
 752 /*
 753  * identify as internal program
 754  */
 755 void cmd_ipgm(char *argbuf)
 756 {
 757         int secret;
 758
 759         secret = extract_int(argbuf, 0);
 760
 761         /* For security reasons, we do NOT allow this command to run
 762          * over the network.  Local sockets only.
 763          */
 764         if (!CC->is_local_socket) {
 765                 sleep(5);
 766                 cprintf("%d Authentication failed.\n",ERROR);
 767         }
 768         else if (secret == config.c_ipgm_secret) {
 769                 CC->internal_pgm = 1;
 770                 strcpy(CC->curr_user, "<internal program>");
 771                 CC->cs_flags = CC->cs_flags|CS_STEALTH;
 772                 cprintf("%d Authenticated as an internal program.\n", CIT_OK);
 773         }
 774         else {
 775                 sleep(5);
 776                 cprintf("%d Authentication failed.\n",ERROR);
 777                 lprintf(3, "Warning: ipgm authentication failed.\n");
 778                 CC->kill_me = 1;
 779         }
 780
 781         /* Now change the ipgm secret for the next round. */
 782         get_config();
 783         config.c_ipgm_secret = rand();
 784         put_config();
 785 }
 786
 787
 788 /*
 789  * Shut down the server
 790  */
 791 void cmd_down(void) {
 792
 793         if (CtdlAccessCheck(ac_aide)) return;
 794
 795         cprintf("%d Shutting down server.  Goodbye.\n", CIT_OK);
 796         time_to_die = 1;
 797 }
 798
 799 /*
 800  * Schedule or cancel a server shutdown
 801  */
 802 void cmd_scdn(char *argbuf)
 803 {
 804         int new_state;
 805
 806         if (CtdlAccessCheck(ac_aide)) return;
 807
 808         new_state = extract_int(argbuf, 0);
 809         if ((new_state == 0) || (new_state == 1)) {
 810                 ScheduledShutdown = new_state;
 811         }
 812         cprintf("%d %d\n", CIT_OK, ScheduledShutdown);
 813 }
 814
 815
 816 /*
 817  * Set or unset asynchronous protocol mode
 818  */
 819 void cmd_asyn(char *argbuf)
 820 {
 821         int new_state;
 822
 823         new_state = extract_int(argbuf, 0);
 824         if ((new_state == 0) || (new_state == 1)) {
 825                 CC->is_async = new_state;
 826         }
 827         cprintf("%d %d\n", CIT_OK, CC->is_async);
 828 }
 829
 830
 831 /*
 832  * Generate a "nonce" for APOP-style authentication.
 833  *
 834  * RFC 1725 et al specify a PID to be placed in front of the nonce.
 835  * Quoth BTX: That would be stupid.
 836  */
 837 void generate_nonce(struct CitContext *con) {
 838         struct timeval tv;
 839
 840         memset(con->cs_nonce, NONCE_SIZE, 0);
 841         gettimeofday(&tv, NULL);
 842         memset(con->cs_nonce, NONCE_SIZE, 0);
 843         snprintf(con->cs_nonce, NONCE_SIZE, "<%d%ld@%s>",
 844                 rand(), (long)tv.tv_usec, config.c_fqdn);
 845 }
 846
 847
 848
 849
 850 /*
 851  * Back-end function for starting a session
 852  */
 853 void begin_session(struct CitContext *con)
 854 {
 855         int len;        /* should be socklen_t but doesn't work on Macintosh */
 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         strcpy(con->fake_username, "");
 873         strcpy(con->fake_postname, "");
 874         strcpy(con->fake_hostname, "");
 875         strcpy(con->fake_roomname, "");
 876         generate_nonce(con);
 877         snprintf(con->temp, sizeof con->temp, tmpnam(NULL));
 878         safestrncpy(con->cs_host, config.c_fqdn, sizeof con->cs_host);
 879         safestrncpy(con->cs_addr, "", sizeof con->cs_addr);
 880         con->cs_host[sizeof con->cs_host - 1] = 0;
 881         len = sizeof sin;
 882         if (!CC->is_local_socket) {
 883                 if (!getpeername(con->client_socket,
 884                    (struct sockaddr *) &sin, &len))
 885                         locate_host(con->cs_host, sizeof con->cs_host,
 886                                 con->cs_addr, sizeof con->cs_addr,
 887                                 &sin.sin_addr);
 888         }
 889         else {
 890                 strcpy(con->cs_host, "");
 891         }
 892         con->cs_flags = 0;
 893         con->upload_type = UPL_FILE;
 894         con->dl_is_net = 0;
 895         con->FirstSessData = NULL;
 896
 897         con->nologin = 0;
 898         if ((config.c_maxsessions > 0)&&(num_sessions > config.c_maxsessions))
 899                 con->nologin = 1;
 900
 901         lprintf(3, "Session %d: started.\n", con->cs_pid);
 902
 903         /* Run any session startup routines registered by loadable modules */
 904         PerformSessionHooks(EVT_START);
 905 }
 906
 907
 908 void citproto_begin_session() {
 909         if (CC->nologin==1) {
 910                 cprintf("%d %s: Too many users are already online "
 911                         "(maximum is %d)\n",
 912                         ERROR+MAX_SESSIONS_EXCEEDED,
 913                         config.c_nodename, config.c_maxsessions);
 914         }
 915         else {
 916                 cprintf("%d %s Citadel/UX server ready.\n",
 917                         CIT_OK, config.c_nodename);
 918         }
 919 }
 920
 921
 922
 923
 924 /*
 925  * This loop recognizes all server commands.
 926  */
 927 void do_command_loop(void) {
 928         char cmdbuf[SIZ];
 929
 930         time(&CC->lastcmd);
 931         memset(cmdbuf, 0, sizeof cmdbuf); /* Clear it, just in case */
 932         if (client_gets(cmdbuf) < 1) {
 933                 lprintf(3, "Client socket is broken.  Ending session.\n");
 934                 CC->kill_me = 1;
 935                 return;
 936         }
 937         lprintf(5, "Citadel: %s\n", cmdbuf);
 938
 939         /*
 940          * Let other clients see the last command we executed, and
 941          * update the idle time, but not NOOP, QNOP, PEXP, or GEXP.
 942          */
 943         if ( (strncasecmp(cmdbuf, "NOOP", 4))
 944            && (strncasecmp(cmdbuf, "QNOP", 4))
 945            && (strncasecmp(cmdbuf, "PEXP", 4))
 946            && (strncasecmp(cmdbuf, "GEXP", 4)) ) {
 947                 strcpy(CC->lastcmdname, "    ");
 948                 safestrncpy(CC->lastcmdname, cmdbuf,
 949                         sizeof(CC->lastcmdname) );
 950                 time(&CC->lastidle);
 951         }
 952
 953         if ((strncasecmp(cmdbuf, "ENT0", 4))
 954            && (strncasecmp(cmdbuf, "MESG", 4))
 955            && (strncasecmp(cmdbuf, "MSGS", 4)))
 956         {
 957            CC->cs_flags &= ~CS_POSTING;
 958         }
 959
 960         if (!strncasecmp(cmdbuf,"NOOP",4)) {
 961                 cprintf("%d%cok\n",CIT_OK,CtdlCheckExpress());
 962         }
 963
 964         else if (!strncasecmp(cmdbuf,"QNOP",4)) {
 965                 /* do nothing, this command returns no response */
 966         }
 967
 968         else if (!strncasecmp(cmdbuf,"QUIT",4)) {
 969                 cprintf("%d Goodbye.\n",CIT_OK);
 970                 CC->kill_me = 1;
 971         }
 972
 973         else if (!strncasecmp(cmdbuf,"ASYN",4)) {
 974                 cmd_asyn(&cmdbuf[5]);
 975         }
 976
 977         else if (!strncasecmp(cmdbuf,"LOUT",4)) {
 978                 if (CC->logged_in) logout(CC);
 979                 cprintf("%d logged out.\n",CIT_OK);
 980         }
 981
 982         else if (!strncasecmp(cmdbuf,"USER",4)) {
 983                 cmd_user(&cmdbuf[5]);
 984         }
 985
 986         else if (!strncasecmp(cmdbuf,"PASS",4)) {
 987                 cmd_pass(&cmdbuf[5]);
 988         }
 989
 990         else if (!strncasecmp(cmdbuf,"NEWU",4)) {
 991                 cmd_newu(&cmdbuf[5]);
 992         }
 993
 994         else if (!strncasecmp(cmdbuf,"CREU",4)) {
 995                 cmd_creu(&cmdbuf[5]);
 996         }
 997
 998         else if (!strncasecmp(cmdbuf,"SETP",4)) {
 999                 cmd_setp(&cmdbuf[5]);
1000         }
1001
1002         else if (!strncasecmp(cmdbuf,"LRMS",4)) {
1003                 cmd_lrms(&cmdbuf[5]);
1004         }
1005
1006         else if (!strncasecmp(cmdbuf,"LKRA",4)) {
1007                 cmd_lkra(&cmdbuf[5]);
1008         }
1009
1010         else if (!strncasecmp(cmdbuf,"LKRN",4)) {
1011                 cmd_lkrn(&cmdbuf[5]);
1012         }
1013
1014         else if (!strncasecmp(cmdbuf,"LKRO",4)) {
1015                 cmd_lkro(&cmdbuf[5]);
1016         }
1017
1018         else if (!strncasecmp(cmdbuf,"LZRM",4)) {
1019                 cmd_lzrm(&cmdbuf[5]);
1020         }
1021
1022         else if (!strncasecmp(cmdbuf,"LPRM",4)) {
1023                 cmd_lprm(&cmdbuf[5]);
1024         }
1025
1026         else if (!strncasecmp(cmdbuf,"GETU",4)) {
1027                 cmd_getu();
1028         }
1029
1030         else if (!strncasecmp(cmdbuf,"SETU",4)) {
1031                 cmd_setu(&cmdbuf[5]);
1032         }
1033
1034         else if (!strncasecmp(cmdbuf,"GOTO",4)) {
1035                 cmd_goto(&cmdbuf[5]);
1036         }
1037
1038         else if (!strncasecmp(cmdbuf,"MSGS",4)) {
1039                 cmd_msgs(&cmdbuf[5]);
1040         }
1041
1042         else if (!strncasecmp(cmdbuf,"WHOK",4)) {
1043                 cmd_whok();
1044         }
1045
1046         else if (!strncasecmp(cmdbuf,"RDIR",4)) {
1047                 cmd_rdir();
1048         }
1049
1050         else if (!strncasecmp(cmdbuf,"MSG0",4)) {
1051                 cmd_msg0(&cmdbuf[5]);
1052         }
1053
1054         else if (!strncasecmp(cmdbuf,"MSG2",4)) {
1055                 cmd_msg2(&cmdbuf[5]);
1056         }
1057
1058         else if (!strncasecmp(cmdbuf,"MSG3",4)) {
1059                 cmd_msg3(&cmdbuf[5]);
1060         }
1061
1062         else if (!strncasecmp(cmdbuf,"MSG4",4)) {
1063                 cmd_msg4(&cmdbuf[5]);
1064         }
1065
1066         else if (!strncasecmp(cmdbuf,"MSGP",4)) {
1067                 cmd_msgp(&cmdbuf[5]);
1068         }
1069
1070         else if (!strncasecmp(cmdbuf,"OPNA",4)) {
1071                 cmd_opna(&cmdbuf[5]);
1072         }
1073
1074         else if (!strncasecmp(cmdbuf,"INFO",4)) {
1075                 cmd_info();
1076         }
1077
1078         else if (!strncasecmp(cmdbuf,"SLRP",4)) {
1079                 cmd_slrp(&cmdbuf[5]);
1080         }
1081
1082         else if (!strncasecmp(cmdbuf,"INVT",4)) {
1083                 cmd_invt_kick(&cmdbuf[5],1);
1084         }
1085
1086         else if (!strncasecmp(cmdbuf,"KICK",4)) {
1087                 cmd_invt_kick(&cmdbuf[5],0);
1088         }
1089
1090         else if (!strncasecmp(cmdbuf,"GETR",4)) {
1091                 cmd_getr();
1092         }
1093
1094         else if (!strncasecmp(cmdbuf,"SETR",4)) {
1095                 cmd_setr(&cmdbuf[5]);
1096         }
1097
1098         else if (!strncasecmp(cmdbuf,"GETA",4)) {
1099                 cmd_geta();
1100         }
1101
1102         else if (!strncasecmp(cmdbuf,"SETA",4)) {
1103                 cmd_seta(&cmdbuf[5]);
1104         }
1105
1106         else if (!strncasecmp(cmdbuf,"ENT0",4)) {
1107                 cmd_ent0(&cmdbuf[5]);
1108         }
1109
1110         else if (!strncasecmp(cmdbuf,"RINF",4)) {
1111                 cmd_rinf();
1112         }
1113
1114         else if (!strncasecmp(cmdbuf,"DELE",4)) {
1115                 cmd_dele(&cmdbuf[5]);
1116         }
1117
1118         else if (!strncasecmp(cmdbuf,"KILL",4)) {
1119                 cmd_kill(&cmdbuf[5]);
1120         }
1121
1122         else if (!strncasecmp(cmdbuf,"CRE8",4)) {
1123                 cmd_cre8(&cmdbuf[5]);
1124         }
1125
1126         else if (!strncasecmp(cmdbuf,"MOVE",4)) {
1127                 cmd_move(&cmdbuf[5]);
1128         }
1129
1130         else if (!strncasecmp(cmdbuf,"FORG",4)) {
1131                 cmd_forg();
1132         }
1133
1134         else if (!strncasecmp(cmdbuf,"MESG",4)) {
1135                 cmd_mesg(&cmdbuf[5]);
1136         }
1137
1138         else if (!strncasecmp(cmdbuf,"EMSG",4)) {
1139                 cmd_emsg(&cmdbuf[5]);
1140         }
1141
1142         else if (!strncasecmp(cmdbuf,"GNUR",4)) {
1143                 cmd_gnur();
1144         }
1145
1146         else if (!strncasecmp(cmdbuf,"VALI",4)) {
1147                 cmd_vali(&cmdbuf[5]);
1148         }
1149
1150         else if (!strncasecmp(cmdbuf,"EINF",4)) {
1151                 cmd_einf(&cmdbuf[5]);
1152         }
1153
1154         else if (!strncasecmp(cmdbuf,"LIST",4)) {
1155                 cmd_list();
1156         }
1157
1158         else if (!strncasecmp(cmdbuf,"CHEK",4)) {
1159                 cmd_chek();
1160         }
1161
1162         else if (!strncasecmp(cmdbuf,"DELF",4)) {
1163                 cmd_delf(&cmdbuf[5]);
1164         }
1165
1166         else if (!strncasecmp(cmdbuf,"MOVF",4)) {
1167                 cmd_movf(&cmdbuf[5]);
1168         }
1169
1170         else if (!strncasecmp(cmdbuf,"NETF",4)) {
1171                 cmd_netf(&cmdbuf[5]);
1172         }
1173
1174         else if (!strncasecmp(cmdbuf,"OPEN",4)) {
1175                 cmd_open(&cmdbuf[5]);
1176         }
1177
1178         else if (!strncasecmp(cmdbuf,"CLOS",4)) {
1179                 cmd_clos();
1180         }
1181
1182         else if (!strncasecmp(cmdbuf,"UOPN",4)) {
1183                 cmd_uopn(&cmdbuf[5]);
1184         }
1185
1186         else if (!strncasecmp(cmdbuf,"UCLS",4)) {
1187                 cmd_ucls(&cmdbuf[5]);
1188         }
1189
1190         else if (!strncasecmp(cmdbuf,"READ",4)) {
1191                 cmd_read(&cmdbuf[5]);
1192         }
1193
1194         else if (!strncasecmp(cmdbuf,"WRIT",4)) {
1195                 cmd_writ(&cmdbuf[5]);
1196         }
1197
1198         else if (!strncasecmp(cmdbuf,"QUSR",4)) {
1199                 cmd_qusr(&cmdbuf[5]);
1200         }
1201
1202         else if (!strncasecmp(cmdbuf,"ECHO",4)) {
1203                 cmd_echo(&cmdbuf[5]);
1204         }
1205
1206         else if (!strncasecmp(cmdbuf,"OIMG",4)) {
1207                 cmd_oimg(&cmdbuf[5]);
1208         }
1209
1210         else if (!strncasecmp(cmdbuf,"MORE",4)) {
1211                 cmd_more();
1212         }
1213
1214         else if (!strncasecmp(cmdbuf,"NDOP",4)) {
1215                 cmd_ndop(&cmdbuf[5]);
1216         }
1217
1218         else if (!strncasecmp(cmdbuf,"NUOP",4)) {
1219                 cmd_nuop(&cmdbuf[5]);
1220         }
1221
1222         else if (!strncasecmp(cmdbuf,"LFLR",4)) {
1223                 cmd_lflr();
1224         }
1225
1226         else if (!strncasecmp(cmdbuf,"CFLR",4)) {
1227                 cmd_cflr(&cmdbuf[5]);
1228         }
1229
1230         else if (!strncasecmp(cmdbuf,"KFLR",4)) {
1231                 cmd_kflr(&cmdbuf[5]);
1232         }
1233
1234         else if (!strncasecmp(cmdbuf,"EFLR",4)) {
1235                 cmd_eflr(&cmdbuf[5]);
1236         }
1237
1238         else if (!strncasecmp(cmdbuf,"IDEN",4)) {
1239                 cmd_iden(&cmdbuf[5]);
1240         }
1241
1242         else if (!strncasecmp(cmdbuf,"IPGM",4)) {
1243                 cmd_ipgm(&cmdbuf[5]);
1244         }
1245
1246         else if (!strncasecmp(cmdbuf,"TERM",4)) {
1247                 cmd_term(&cmdbuf[5]);
1248         }
1249
1250         else if (!strncasecmp(cmdbuf,"DOWN",4)) {
1251                 cmd_down();
1252         }
1253
1254         else if (!strncasecmp(cmdbuf,"SCDN",4)) {
1255                 cmd_scdn(&cmdbuf[5]);
1256         }
1257
1258         else if (!strncasecmp(cmdbuf, "UIMG", 4)) {
1259                 cmd_uimg(&cmdbuf[5]);
1260         }
1261
1262         else if (!strncasecmp(cmdbuf, "TIME", 4)) {
1263                 cmd_time();
1264         }
1265
1266         else if (!strncasecmp(cmdbuf, "AGUP", 4)) {
1267                 cmd_agup(&cmdbuf[5]);
1268         }
1269
1270         else if (!strncasecmp(cmdbuf, "ASUP", 4)) {
1271                 cmd_asup(&cmdbuf[5]);
1272         }
1273
1274         else if (!strncasecmp(cmdbuf, "GPEX", 4)) {
1275                 cmd_gpex(&cmdbuf[5]);
1276         }
1277
1278         else if (!strncasecmp(cmdbuf, "SPEX", 4)) {
1279                 cmd_spex(&cmdbuf[5]);
1280         }
1281
1282         else if (!strncasecmp(cmdbuf, "CONF", 4)) {
1283                 cmd_conf(&cmdbuf[5]);
1284         }
1285
1286         else if (!strncasecmp(cmdbuf, "SEEN", 4)) {
1287                 cmd_seen(&cmdbuf[5]);
1288         }
1289
1290         else if (!strncasecmp(cmdbuf, "GTSN", 4)) {
1291                 cmd_gtsn(&cmdbuf[5]);
1292         }
1293
1294         else if (!strncasecmp(cmdbuf, "VIEW", 4)) {
1295                 cmd_view(&cmdbuf[5]);
1296         }
1297
1298         else if (!strncasecmp(cmdbuf, "ISME", 4)) {
1299                 cmd_isme(&cmdbuf[5]);
1300         }
1301
1302 #ifdef DEBUG_MEMORY_LEAKS
1303         else if (!strncasecmp(cmdbuf, "LEAK", 4)) {
1304                 dump_tracked();
1305         }
1306 #endif
1307
1308         else if (!DLoader_Exec_Cmd(cmdbuf)) {
1309                 cprintf("%d Unrecognized or unsupported command.\n", ERROR);
1310                }
1311
1312         /* Run any after-each-command outines registered by modules */
1313         PerformSessionHooks(EVT_CMD);
1314 }