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