citadel/citserver.c

   1 /*
   2  * $Id$
   3  *
   4  * Main source module for the Citadel server
   5  *
   6  */
   7
   8 #include "sysdep.h"
   9 #include <stdlib.h>
  10 #include <unistd.h>
  11 #include <stdio.h>
  12 #include <fcntl.h>
  13 #include <signal.h>
  14 #include <sys/types.h>
  15 #include <sys/stat.h>
  16
  17
  18 #if TIME_WITH_SYS_TIME
  19 # include <sys/time.h>
  20 # include <time.h>
  21 #else
  22 # if HAVE_SYS_TIME_H
  23 #  include <sys/time.h>
  24 # else
  25 #  include <time.h>
  26 # endif
  27 #endif
  28
  29 #include <ctype.h>
  30 #include <string.h>
  31 #include <dirent.h>
  32 #include <errno.h>
  33 #include <limits.h>
  34 #include <netdb.h>
  35 #include <sys/types.h>
  36 #include <sys/socket.h>
  37 #include <netinet/in.h>
  38 #include <arpa/inet.h>
  39 #include "citadel.h"
  40 #include "server.h"
  41 #include "serv_extensions.h"
  42 #include "sysdep_decls.h"
  43 #include "citserver.h"
  44 #include "config.h"
  45 #include "database.h"
  46 #include "housekeeping.h"
  47 #include "user_ops.h"
  48 #include "msgbase.h"
  49 #include "support.h"
  50 #include "locate_host.h"
  51 #include "room_ops.h"
  52 #include "file_ops.h"
  53 #include "policy.h"
  54 #include "control.h"
  55 #include "tools.h"
  56 #include "euidindex.h"
  57
  58 #ifndef HAVE_SNPRINTF
  59 #include "snprintf.h"
  60 #endif
  61
  62 struct CitContext *ContextList = NULL;
  63 struct CitContext* next_session = NULL;
  64 char *unique_session_numbers;
  65 int ScheduledShutdown = 0;
  66 int do_defrag = 0;
  67 time_t server_startup_time;
  68 char pid_file_name[PATH_MAX];
  69
  70 /*
  71  * Various things that need to be initialized at startup
  72  */
  73 void master_startup(void) {
  74         struct timeval tv;
  75         unsigned int seed;
  76         FILE *urandom;
  77         struct ctdlroom qrbuf;
  78         FILE *pidfile_fp;
  79
  80         lprintf(CTDL_DEBUG, "master_startup() started\n");
  81         time(&server_startup_time);
  82
  83         /* pid file.  If we go FSSTND this should end up in 'localstatedir' */
  84         snprintf(pid_file_name, sizeof pid_file_name, "./citadel.pid");
  85         pidfile_fp = fopen(pid_file_name, "w");
  86         if (pidfile_fp != NULL) {
  87                 fprintf(pidfile_fp, "%d\n", (int)getpid());
  88                 fclose(pidfile_fp);
  89         }
  90
  91         lprintf(CTDL_INFO, "Opening databases\n");
  92         open_databases();
  93
  94         if (do_defrag) {
  95                 defrag_databases();
  96         }
  97
  98         check_ref_counts();
  99
 100         lprintf(CTDL_INFO, "Creating base rooms (if necessary)\n");
 101         create_room(config.c_baseroom,  0, "", 0, 1, 0, VIEW_BBS);
 102         create_room(AIDEROOM,           3, "", 0, 1, 0, VIEW_BBS);
 103         create_room(SYSCONFIGROOM,      3, "", 0, 1, 0, VIEW_BBS);
 104         create_room(config.c_twitroom,  0, "", 0, 1, 0, VIEW_BBS);
 105
 106         /* The "Local System Configuration" room doesn't need to be visible */
 107         if (lgetroom(&qrbuf, SYSCONFIGROOM) == 0) {
 108                 qrbuf.QRflags2 |= QR2_SYSTEM;
 109                 lputroom(&qrbuf);
 110         }
 111
 112         /*
 113          * Create a room in which we can deposit "deleted" messages for
 114          * deferred deletion.  This will silently fail if the room already
 115          * exists, and that's perfectly ok, because we want it to exist.
 116          */
 117         create_room(DELETED_MSGS_ROOM, 3, "", 0, 1, 0, VIEW_MAILBOX);
 118
 119         /*
 120          * Make sure it's set to be a "system room" so it doesn't show up
 121          * in the <K>nown rooms list for Aides.  Also set the message expire
 122          * policy to "by count, 1 message" so everything gets deleted all
 123          * the time (we can't set it to 0 because that's invalid, so we keep
 124          * a single message around).
 125          */
 126         if (lgetroom(&qrbuf, DELETED_MSGS_ROOM) == 0) {
 127                 qrbuf.QRflags2 |= QR2_SYSTEM;
 128                 qrbuf.QRep.expire_mode = EXPIRE_NUMMSGS;
 129                 qrbuf.QRep.expire_value = 1;
 130                 lputroom(&qrbuf);
 131         }
 132
 133         lprintf(CTDL_INFO, "Seeding the pseudo-random number generator...\n");
 134         urandom = fopen("/dev/urandom", "r");
 135         if (urandom != NULL) {
 136                 fread(&seed, sizeof seed, 1, urandom);
 137                 fclose(urandom);
 138         }
 139         else {
 140                 gettimeofday(&tv, NULL);
 141                 seed = tv.tv_usec;
 142         }
 143         srandom(seed);
 144
 145         lprintf(CTDL_INFO, "Initializing ipgm secret\n");
 146         get_config();
 147         config.c_ipgm_secret = rand();
 148         put_config();
 149
 150         lprintf(CTDL_DEBUG, "master_startup() finished\n");
 151 }
 152
 153
 154 /*
 155  * Cleanup routine to be called when the server is shutting down.
 156  */
 157 void master_cleanup(int exitcode) {
 158         struct CleanupFunctionHook *fcn;
 159         static int already_cleaning_up = 0;
 160
 161         if (already_cleaning_up) while(1) sleep(1);
 162         already_cleaning_up = 1;
 163
 164         /* Run any cleanup routines registered by loadable modules */
 165         for (fcn = CleanupHookTable; fcn != NULL; fcn = fcn->next) {
 166                 (*fcn->h_function_pointer)();
 167         }
 168
 169         /* Shut down the indexer thread */
 170         lprintf(CTDL_INFO, "Waiting for the indexer thread to shut down\n");
 171         pthread_join(indexer_thread_tid, NULL);
 172
 173         /* Shut down the checkpoint thread */
 174         lprintf(CTDL_INFO, "Waiting for the checkpoint thread to shut down\n");
 175         pthread_join(checkpoint_thread_tid, NULL);
 176
 177         /* Close databases */
 178         lprintf(CTDL_INFO, "Closing databases\n");
 179         close_databases();
 180
 181         /* Do system-dependent stuff */
 182         sysdep_master_cleanup();
 183
 184 #ifdef DEBUG_MEMORY_LEAKS
 185         dump_heap();
 186 #endif
 187
 188         /* If the operator requested a halt but not an exit, halt here. */
 189         if (shutdown_and_halt) {
 190                 lprintf(CTDL_NOTICE, "citserver: Halting server without exiting.\n");
 191                 fflush(stdout); fflush(stderr);
 192                 while(1) {
 193                         sleep(32767);
 194                 }
 195         }
 196
 197         /* Now go away. */
 198         lprintf(CTDL_NOTICE, "citserver: Exiting with status %d\n", exitcode);
 199         fflush(stdout); fflush(stderr);
 200
 201         unlink(pid_file_name);
 202         exit(exitcode);
 203 }
 204
 205
 206
 207 /*
 208  * Terminate a session.
 209  */
 210 void RemoveContext (struct CitContext *con)
 211 {
 212         if (con==NULL) {
 213                 lprintf(CTDL_ERR,
 214                         "WARNING: RemoveContext() called with NULL!\n");
 215                 return;
 216         }
 217         lprintf(CTDL_DEBUG, "RemoveContext() session %d\n", con->cs_pid);
 218
 219         /* Run any cleanup routines registered by loadable modules.
 220          * Note: We have to "become_session()" because the cleanup functions
 221          *       might make references to "CC" assuming it's the right one.
 222          */
 223         become_session(con);
 224         PerformSessionHooks(EVT_STOP);
 225         become_session(NULL);
 226
 227         /* Now handle all of the administrivia. */
 228         lprintf(CTDL_DEBUG, "Calling logout(%d)\n", con->cs_pid);
 229         logout(con);
 230
 231         lprintf(CTDL_NOTICE, "[%3d] Session ended.\n", con->cs_pid);
 232
 233         /* If the client is still connected, blow 'em away. */
 234         lprintf(CTDL_DEBUG, "Closing socket %d\n", con->client_socket);
 235         close(con->client_socket);
 236
 237         lprintf(CTDL_DEBUG, "Done with RemoveContext()\n");
 238 }
 239
 240
 241
 242
 243
 244 /*
 245  * cmd_info()  -  tell the client about this server
 246  */
 247 void cmd_info(void) {
 248         cprintf("%d Server info:\n", LISTING_FOLLOWS);
 249         cprintf("%d\n", CC->cs_pid);
 250         cprintf("%s\n", config.c_nodename);
 251         cprintf("%s\n", config.c_humannode);
 252         cprintf("%s\n", config.c_fqdn);
 253         cprintf("%s\n", CITADEL);
 254         cprintf("%d\n", REV_LEVEL);
 255         cprintf("%s\n", config.c_site_location);
 256         cprintf("%s\n", config.c_sysadm);
 257         cprintf("%d\n", SERVER_TYPE);
 258         cprintf("%s\n", config.c_moreprompt);
 259         cprintf("1\n"); /* 1 = yes, this system supports floors */
 260         cprintf("1\n"); /* 1 = we support the extended paging options */
 261         cprintf("%s\n", CC->cs_nonce);
 262         cprintf("1\n"); /* 1 = yes, this system supports the QNOP command */
 263
 264 #ifdef HAVE_LDAP
 265         cprintf("1\n"); /* 1 = yes, this server is LDAP-enabled */
 266 #else
 267         cprintf("0\n"); /* 1 = no, this server is not LDAP-enabled */
 268 #endif
 269
 270 #ifdef ENABLE_AUTOLOGIN
 271         cprintf("1\n"); /* "create new user" never works with autologin */
 272 #else
 273         cprintf("%d\n", config.c_disable_newu); /* otherwise, site defined */
 274 #endif
 275
 276         cprintf("000\n");
 277 }
 278
 279
 280 /*
 281  * returns an asterisk if there are any instant messages waiting,
 282  * space otherwise.
 283  */
 284 char CtdlCheckExpress(void) {
 285         if (CC->FirstExpressMessage == NULL) {
 286                 return(' ');
 287         }
 288         else {
 289                 return('*');
 290         }
 291 }
 292
 293 void cmd_time(void)
 294 {
 295    time_t tv;
 296    struct tm tmp;
 297
 298    tv = time(NULL);
 299    localtime_r(&tv, &tmp);
 300
 301    /* timezone and daylight global variables are not portable. */
 302 #ifdef HAVE_STRUCT_TM_TM_GMTOFF
 303    cprintf("%d %ld|%ld|%d\n", CIT_OK, (long)tv, tmp.tm_gmtoff, tmp.tm_isdst);
 304 #else
 305    cprintf("%d %ld|%ld|%d\n", CIT_OK, (long)tv, timezone, tmp.tm_isdst);
 306 #endif
 307 }
 308
 309
 310 /*
 311  * Check originating host against the public_clients file.  This determines
 312  * whether the client is allowed to change the hostname for this session
 313  * (for example, to show the location of the user rather than the location
 314  * of the client).
 315  */
 316 int is_public_client(void)
 317 {
 318         char buf[1024];
 319         char addrbuf[1024];
 320         FILE *fp;
 321         int i;
 322         struct stat statbuf;
 323         static time_t pc_timestamp = 0;
 324         static char public_clients[SIZ];
 325         static char public_clients_file[SIZ];
 326
 327         snprintf(public_clients_file,
 328                          sizeof public_clients_file,
 329                          "%s/public_clients",
 330                          ctdl_etc_dir);
 331
 332         /*
 333          * Check the time stamp on the public_clients file.  If it's been
 334          * updated since the last time we were here (or if this is the first
 335          * time we've been through the loop), read its contents and learn
 336          * the IP addresses of the listed hosts.
 337          */
 338         if (stat(public_clients_file, &statbuf) != 0) {
 339                 /* No public_clients file exists, so bail out */
 340                 lprintf(CTDL_WARNING, "Warning: '%s' does not exist\n",
 341                                 public_clients_file);
 342                 return(0);
 343         }
 344
 345         if (statbuf.st_mtime > pc_timestamp) {
 346                 begin_critical_section(S_PUBLIC_CLIENTS);
 347                 lprintf(CTDL_INFO, "Loading %s\n", public_clients_file);
 348
 349                 safestrncpy(public_clients, "127.0.0.1", sizeof public_clients);
 350                 if (hostname_to_dotted_quad(addrbuf, config.c_fqdn) == 0) {
 351                         strcat(public_clients, "|");
 352                         strcat(public_clients, addrbuf);
 353                 }
 354
 355                 fp = fopen(public_clients_file, "r");
 356                 if (fp != NULL) while (fgets(buf, sizeof buf, fp)!=NULL) {
 357                         for (i=0; i<strlen(buf); ++i) {
 358                                 if (buf[i] == '#') buf[i] = 0;
 359                         }
 360                         while (isspace((buf[strlen(buf)-1]))) {
 361                                 buf[strlen(buf)-1] = 0;
 362                         }
 363                         if (hostname_to_dotted_quad(addrbuf, buf) == 0) {
 364                                 if ((strlen(public_clients) +
 365                                    strlen(addrbuf) + 2)
 366                                    < sizeof(public_clients)) {
 367                                         strcat(public_clients, addrbuf);
 368                                 }
 369                         }
 370                 }
 371                 fclose(fp);
 372                 pc_timestamp = time(NULL);
 373                 end_critical_section(S_PUBLIC_CLIENTS);
 374         }
 375
 376         lprintf(CTDL_DEBUG, "Checking whether %s is a local or public client\n",
 377                 CC->cs_addr);
 378         for (i=0; i<num_parms(public_clients); ++i) {
 379                 extract_token(addrbuf, public_clients, i, '|', sizeof addrbuf);
 380                 if (!strcasecmp(CC->cs_addr, addrbuf)) {
 381                         lprintf(CTDL_DEBUG, "... yes it is.\n");
 382                         return(1);
 383                 }
 384         }
 385
 386         /* No hits.  This is not a public client. */
 387         lprintf(CTDL_DEBUG, "... no it isn't.\n");
 388         return(0);
 389 }
 390
 391
 392 /*
 393  * the client is identifying itself to the server
 394  */
 395 void cmd_iden(char *argbuf)
 396 {
 397         int dev_code;
 398         int cli_code;
 399         int rev_level;
 400         char desc[128];
 401         char from_host[128];
 402         struct in_addr addr;
 403         int do_lookup = 0;
 404
 405         if (num_parms(argbuf)<4) {
 406                 cprintf("%d usage error\n", ERROR + ILLEGAL_VALUE);
 407                 return;
 408         }
 409
 410         dev_code = extract_int(argbuf,0);
 411         cli_code = extract_int(argbuf,1);
 412         rev_level = extract_int(argbuf,2);
 413         extract_token(desc, argbuf, 3, '|', sizeof desc);
 414
 415         safestrncpy(from_host, config.c_fqdn, sizeof from_host);
 416         from_host[sizeof from_host - 1] = 0;
 417         if (num_parms(argbuf)>=5) extract_token(from_host, argbuf, 4, '|', sizeof from_host);
 418
 419         CC->cs_clientdev = dev_code;
 420         CC->cs_clienttyp = cli_code;
 421         CC->cs_clientver = rev_level;
 422         safestrncpy(CC->cs_clientname, desc, sizeof CC->cs_clientname);
 423         CC->cs_clientname[31] = 0;
 424
 425         if (strlen(from_host) > 0) {
 426                 if (CC->is_local_socket) do_lookup = 1;
 427                 else if (is_public_client()) do_lookup = 1;
 428         }
 429
 430         if (do_lookup) {
 431                 lprintf(CTDL_DEBUG, "Looking up hostname '%s'\n", from_host);
 432                 if ((addr.s_addr = inet_addr(from_host)) != -1) {
 433                         locate_host(CC->cs_host, sizeof CC->cs_host,
 434                                 NULL, 0,
 435                                 &addr);
 436                 }
 437                 else {
 438                         safestrncpy(CC->cs_host, from_host, sizeof CC->cs_host);
 439                         CC->cs_host[sizeof CC->cs_host - 1] = 0;
 440                 }
 441         }
 442
 443         lprintf(CTDL_NOTICE, "Client %d/%d/%01d.%02d (%s) from %s\n",
 444                 dev_code,
 445                 cli_code,
 446                 (rev_level / 100),
 447                 (rev_level % 100),
 448                 desc,
 449                 CC->cs_host);
 450         cprintf("%d Ok\n",CIT_OK);
 451 }
 452
 453
 454 /*
 455  * display system messages or help
 456  */
 457 void cmd_mesg(char *mname)
 458 {
 459         FILE *mfp;
 460         char targ[256];
 461         char buf[256];
 462         char buf2[256];
 463         char *dirs[2];
 464         DIR *dp;
 465         struct dirent *d;
 466
 467         extract_token(buf, mname, 0, '|', sizeof buf);
 468
 469         dirs[0] = strdup(ctdl_message_dir);
 470         dirs[1] = strdup(ctdl_hlp_dir);
 471
 472         snprintf(buf2, sizeof buf2, "%s.%d.%d",
 473                 buf, CC->cs_clientdev, CC->cs_clienttyp);
 474
 475         /* If the client requested "?" then produce a listing */
 476         if (!strcmp(buf, "?")) {
 477                 cprintf("%d %s\n", LISTING_FOLLOWS, buf);
 478                 dp = opendir(dirs[1]);
 479                 if (dp != NULL) {
 480                         while (d = readdir(dp), d != NULL) {
 481                                 if (d->d_name[0] != '.') {
 482                                         cprintf(" %s\n", d->d_name);
 483                                 }
 484                         }
 485                         closedir(dp);
 486                 }
 487                 cprintf("000\n");
 488                 free(dirs[0]);
 489                 free(dirs[1]);
 490                 return;
 491         }
 492
 493         /* Otherwise, look for the requested file by name. */
 494         else {
 495                 mesg_locate(targ, sizeof targ, buf2, 2, (const char **)dirs);
 496                 if (strlen(targ) == 0) {
 497                         snprintf(buf2, sizeof buf2, "%s.%d",
 498                                                         buf, CC->cs_clientdev);
 499                         mesg_locate(targ, sizeof targ, buf2, 2,
 500                                                         (const char **)dirs);
 501                         if (strlen(targ) == 0) {
 502                                 mesg_locate(targ, sizeof targ, buf, 2,
 503                                                         (const char **)dirs);
 504                         }
 505                 }
 506         }
 507
 508         free(dirs[0]);
 509         free(dirs[1]);
 510
 511         if (strlen(targ)==0) {
 512                 cprintf("%d '%s' not found.  (Searching in %s and %s)\n",
 513                         ERROR + FILE_NOT_FOUND,
 514                         mname,
 515                         ctdl_message_dir,
 516                         ctdl_hlp_dir
 517                 );
 518                 return;
 519         }
 520
 521         mfp = fopen(targ, "r");
 522         if (mfp==NULL) {
 523                 cprintf("%d Cannot open '%s': %s\n",
 524                         ERROR + INTERNAL_ERROR, targ, strerror(errno));
 525                 return;
 526         }
 527         cprintf("%d %s\n", LISTING_FOLLOWS,buf);
 528
 529         while (fgets(buf, (sizeof buf - 1), mfp) != NULL) {
 530                 buf[strlen(buf)-1] = 0;
 531                 do_help_subst(buf);
 532                 cprintf("%s\n",buf);
 533         }
 534
 535         fclose(mfp);
 536         cprintf("000\n");
 537 }
 538
 539
 540 /*
 541  * enter system messages or help
 542  */
 543 void cmd_emsg(char *mname)
 544 {
 545         FILE *mfp;
 546         char targ[256];
 547         char buf[256];
 548         char *dirs[2];
 549         int a;
 550
 551         unbuffer_output();
 552
 553         if (CtdlAccessCheck(ac_aide)) return;
 554
 555         extract_token(buf, mname, 0, '|', sizeof buf);
 556         for (a=0; a<strlen(buf); ++a) {         /* security measure */
 557                 if (buf[a] == '/') buf[a] = '.';
 558         }
 559
 560         dirs[0] = strdup(ctdl_message_dir);
 561         dirs[1] = strdup(ctdl_hlp_dir);
 562
 563         mesg_locate(targ, sizeof targ, buf, 2, (const char**)dirs);
 564         free(dirs[0]);
 565         free(dirs[1]);
 566
 567         if (strlen(targ)==0) {
 568                 snprintf(targ, sizeof targ,
 569                                  "%s/%s",
 570                                  ctdl_hlp_dir, buf);
 571         }
 572
 573         mfp = fopen(targ,"w");
 574         if (mfp==NULL) {
 575                 cprintf("%d Cannot open '%s': %s\n",
 576                         ERROR + INTERNAL_ERROR, targ, strerror(errno));
 577                 return;
 578         }
 579         cprintf("%d %s\n", SEND_LISTING, targ);
 580
 581         while (client_getln(buf, sizeof buf), strcmp(buf, "000")) {
 582                 fprintf(mfp, "%s\n", buf);
 583         }
 584
 585         fclose(mfp);
 586 }
 587
 588
 589 /* Don't show the names of private rooms unless the viewing
 590  * user also knows the rooms.
 591  */
 592 void GenerateRoomDisplay(char *real_room,
 593                         struct CitContext *viewed,
 594                         struct CitContext *viewer) {
 595
 596         int ra;
 597
 598         strcpy(real_room, viewed->room.QRname);
 599         if (viewed->room.QRflags & QR_MAILBOX) {
 600                 strcpy(real_room, &real_room[11]);
 601         }
 602         if (viewed->room.QRflags & QR_PRIVATE) {
 603                 CtdlRoomAccess(&viewed->room, &viewer->user, &ra, NULL);
 604                 if ( (ra & UA_KNOWN) == 0) {
 605                         strcpy(real_room, "<private room>");
 606                 }
 607         }
 608
 609         if (viewed->cs_flags & CS_CHAT) {
 610                 while (strlen(real_room) < 14)
 611                         strcat(real_room, " ");
 612
 613                 strcpy(&real_room[14], "<chat>");
 614         }
 615
 616 }
 617
 618 /*
 619  * Convenience function.
 620  */
 621 int CtdlAccessCheck(int required_level) {
 622
 623         if (CC->internal_pgm) return(0);
 624         if (required_level >= ac_internal) {
 625                 cprintf("%d This is not a user-level command.\n",
 626                         ERROR + HIGHER_ACCESS_REQUIRED);
 627                 return(-1);
 628         }
 629
 630         if ((required_level >= ac_logged_in) && (CC->logged_in == 0)) {
 631                 cprintf("%d Not logged in.\n", ERROR + NOT_LOGGED_IN);
 632                 return(-1);
 633         }
 634
 635         if (CC->user.axlevel >= 6) return(0);
 636         if (required_level >= ac_aide) {
 637                 cprintf("%d This command requires Aide access.\n",
 638                         ERROR + HIGHER_ACCESS_REQUIRED);
 639                 return(-1);
 640         }
 641
 642         if (is_room_aide()) return(0);
 643         if (required_level >= ac_room_aide) {
 644                 cprintf("%d This command requires Aide or Room Aide access.\n",
 645                         ERROR + HIGHER_ACCESS_REQUIRED);
 646                 return(-1);
 647         }
 648
 649         /* shhh ... succeed quietly */
 650         return(0);
 651 }
 652
 653
 654
 655 /*
 656  * Terminate another running session
 657  */
 658 void cmd_term(char *cmdbuf)
 659 {
 660         int session_num;
 661         struct CitContext *ccptr;
 662         int found_it = 0;
 663         int allowed = 0;
 664
 665         session_num = extract_int(cmdbuf, 0);
 666         if (session_num == CC->cs_pid) {
 667                 cprintf("%d You can't kill your own session.\n", ERROR + ILLEGAL_VALUE);
 668                 return;
 669         }
 670
 671         lprintf(CTDL_DEBUG, "Locating session to kill\n");
 672         begin_critical_section(S_SESSION_TABLE);
 673         for (ccptr = ContextList; ccptr != NULL; ccptr = ccptr->next) {
 674                 if (session_num == ccptr->cs_pid) {
 675                         found_it = 1;
 676                         if ((ccptr->user.usernum == CC->user.usernum)
 677                            || (CC->user.axlevel >= 6)) {
 678                                 allowed = 1;
 679                                 ccptr->kill_me = 1;
 680                         }
 681                         else {
 682                                 allowed = 0;
 683                         }
 684                 }
 685         }
 686         end_critical_section(S_SESSION_TABLE);
 687
 688         if (found_it) {
 689                 if (allowed) {
 690                         cprintf("%d Session terminated.\n", CIT_OK);
 691                 }
 692                 else {
 693                         cprintf("%d You are not allowed to do that.\n",
 694                                 ERROR + HIGHER_ACCESS_REQUIRED);
 695                 }
 696         }
 697         else {
 698                 cprintf("%d No such session.\n", ERROR + ILLEGAL_VALUE);
 699         }
 700 }
 701
 702
 703
 704
 705
 706 /*
 707  * get the paginator prompt
 708  */
 709 void cmd_more(void) {
 710         cprintf("%d %s\n", CIT_OK, config.c_moreprompt);
 711 }
 712
 713 /*
 714  * echo
 715  */
 716 void cmd_echo(char *etext)
 717 {
 718         cprintf("%d %s\n", CIT_OK, etext);
 719 }
 720
 721
 722
 723 /*
 724  * identify as internal program
 725  */
 726 void cmd_ipgm(char *argbuf)
 727 {
 728         int secret;
 729
 730         secret = extract_int(argbuf, 0);
 731
 732         /* For security reasons, we do NOT allow this command to run
 733          * over the network.  Local sockets only.
 734          */
 735         if (!CC->is_local_socket) {
 736                 sleep(5);
 737                 cprintf("%d Authentication failed.\n",
 738                         ERROR + PASSWORD_REQUIRED);
 739         }
 740         else if (secret == config.c_ipgm_secret) {
 741                 CC->internal_pgm = 1;
 742                 strcpy(CC->curr_user, "<internal program>");
 743                 CC->cs_flags = CC->cs_flags|CS_STEALTH;
 744                 cprintf("%d Authenticated as an internal program.\n", CIT_OK);
 745         }
 746         else {
 747                 sleep(5);
 748                 cprintf("%d Authentication failed.\n",
 749                         ERROR + PASSWORD_REQUIRED);
 750                 lprintf(CTDL_ERR, "Warning: ipgm authentication failed.\n");
 751                 CC->kill_me = 1;
 752         }
 753
 754         /* Now change the ipgm secret for the next round.
 755          * (Disabled because it breaks concurrent scripts.  The fact that
 756          * we no longer accept IPGM over the network should be sufficient
 757          * to prevent brute-force attacks.  If you don't agree, uncomment
 758          * this block.)
 759         get_config();
 760         config.c_ipgm_secret = rand();
 761         put_config();
 762         */
 763 }
 764
 765
 766 /*
 767  * Shut down the server
 768  */
 769 void cmd_down(void) {
 770
 771         if (CtdlAccessCheck(ac_aide)) return;
 772
 773         cprintf("%d Shutting down server.  Goodbye.\n", CIT_OK);
 774         time_to_die = 1;
 775 }
 776
 777 /*
 778  * Halt the server without exiting the server process.
 779  */
 780 void cmd_halt(void) {
 781
 782         if (CtdlAccessCheck(ac_aide)) return;
 783
 784         cprintf("%d Halting server.  Goodbye.\n", CIT_OK);
 785         time_to_die = 1;
 786         shutdown_and_halt = 1;
 787 }
 788
 789 /*
 790  * Schedule or cancel a server shutdown
 791  */
 792 void cmd_scdn(char *argbuf)
 793 {
 794         int new_state;
 795
 796         if (CtdlAccessCheck(ac_aide)) return;
 797
 798         new_state = extract_int(argbuf, 0);
 799         if ((new_state == 0) || (new_state == 1)) {
 800                 ScheduledShutdown = new_state;
 801         }
 802         cprintf("%d %d\n", CIT_OK, ScheduledShutdown);
 803 }
 804
 805
 806 /*
 807  * Set or unset asynchronous protocol mode
 808  */
 809 void cmd_asyn(char *argbuf)
 810 {
 811         int new_state;
 812
 813         new_state = extract_int(argbuf, 0);
 814         if ((new_state == 0) || (new_state == 1)) {
 815                 CC->is_async = new_state;
 816         }
 817         cprintf("%d %d\n", CIT_OK, CC->is_async);
 818 }
 819
 820
 821 /*
 822  * Generate a "nonce" for APOP-style authentication.
 823  *
 824  * RFC 1725 et al specify a PID to be placed in front of the nonce.
 825  * Quoth BTX: That would be stupid.
 826  */
 827 void generate_nonce(struct CitContext *con) {
 828         struct timeval tv;
 829
 830         memset(con->cs_nonce, NONCE_SIZE, 0);
 831         gettimeofday(&tv, NULL);
 832         memset(con->cs_nonce, NONCE_SIZE, 0);
 833         snprintf(con->cs_nonce, NONCE_SIZE, "<%d%ld@%s>",
 834                 rand(), (long)tv.tv_usec, config.c_fqdn);
 835 }
 836
 837
 838
 839
 840 /*
 841  * Back-end function for starting a session
 842  */
 843 void begin_session(struct CitContext *con)
 844 {
 845         socklen_t len;
 846         struct sockaddr_in sin;
 847
 848         /*
 849          * Initialize some variables specific to our context.
 850          */
 851         con->logged_in = 0;
 852         con->internal_pgm = 0;
 853         con->download_fp = NULL;
 854         con->upload_fp = NULL;
 855         con->FirstExpressMessage = NULL;
 856         time(&con->lastcmd);
 857         time(&con->lastidle);
 858         strcpy(con->lastcmdname, "    ");
 859         strcpy(con->cs_clientname, "(unknown)");
 860         strcpy(con->curr_user, NLI);
 861         strcpy(con->net_node, "");
 862         strcpy(con->fake_username, "");
 863         strcpy(con->fake_postname, "");
 864         strcpy(con->fake_hostname, "");
 865         strcpy(con->fake_roomname, "");
 866         generate_nonce(con);
 867         safestrncpy(con->cs_host, config.c_fqdn, sizeof con->cs_host);
 868         safestrncpy(con->cs_addr, "", sizeof con->cs_addr);
 869         con->cs_host[sizeof con->cs_host - 1] = 0;
 870         len = sizeof sin;
 871         if (!CC->is_local_socket) {
 872                 if (!getpeername(con->client_socket, (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                 }
 878         }
 879         else {
 880                 strcpy(con->cs_host, "");
 881         }
 882         con->cs_flags = 0;
 883         con->upload_type = UPL_FILE;
 884         con->dl_is_net = 0;
 885
 886         con->nologin = 0;
 887         if ((config.c_maxsessions > 0)&&(num_sessions > config.c_maxsessions))
 888                 con->nologin = 1;
 889
 890         lprintf(CTDL_NOTICE, "Session started.\n");
 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 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_getln(cmdbuf, sizeof cmdbuf) < 1) {
 922                 lprintf(CTDL_ERR, "Client disconnected: ending session.\n");
 923                 CC->kill_me = 1;
 924                 return;
 925         }
 926
 927         /* Log the server command, but don't show passwords... */
 928         if ( (strncasecmp(cmdbuf, "PASS", 4))
 929            && (strncasecmp(cmdbuf, "SETP", 4)) ) {
 930                 lprintf(CTDL_INFO, "%s\n", cmdbuf);
 931         }
 932         else {
 933                 lprintf(CTDL_INFO, "<password command sent>\n");
 934         }
 935
 936         buffer_output();
 937
 938         /*
 939          * Let other clients see the last command we executed, and
 940          * update the idle time, but not NOOP, QNOP, PEXP, GEXP, RWHO, or TIME.
 941          */
 942         if ( (strncasecmp(cmdbuf, "NOOP", 4))
 943            && (strncasecmp(cmdbuf, "QNOP", 4))
 944            && (strncasecmp(cmdbuf, "PEXP", 4))
 945            && (strncasecmp(cmdbuf, "GEXP", 4))
 946            && (strncasecmp(cmdbuf, "RWHO", 4))
 947            && (strncasecmp(cmdbuf, "TIME", 4)) ) {
 948                 strcpy(CC->lastcmdname, "    ");
 949                 safestrncpy(CC->lastcmdname, cmdbuf, 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,"EUID",4)) {
1051                 cmd_euid(&cmdbuf[5]);
1052         }
1053
1054         else if (!strncasecmp(cmdbuf,"MSG0",4)) {
1055                 cmd_msg0(&cmdbuf[5]);
1056         }
1057
1058         else if (!strncasecmp(cmdbuf,"MSG2",4)) {
1059                 cmd_msg2(&cmdbuf[5]);
1060         }
1061
1062         else if (!strncasecmp(cmdbuf,"MSG3",4)) {
1063                 cmd_msg3(&cmdbuf[5]);
1064         }
1065
1066         else if (!strncasecmp(cmdbuf,"MSG4",4)) {
1067                 cmd_msg4(&cmdbuf[5]);
1068         }
1069
1070         else if (!strncasecmp(cmdbuf,"MSGP",4)) {
1071                 cmd_msgp(&cmdbuf[5]);
1072         }
1073
1074         else if (!strncasecmp(cmdbuf,"OPNA",4)) {
1075                 cmd_opna(&cmdbuf[5]);
1076         }
1077
1078         else if (!strncasecmp(cmdbuf,"INFO",4)) {
1079                 cmd_info();
1080         }
1081
1082         else if (!strncasecmp(cmdbuf,"SLRP",4)) {
1083                 cmd_slrp(&cmdbuf[5]);
1084         }
1085
1086         else if (!strncasecmp(cmdbuf,"INVT",4)) {
1087                 cmd_invt_kick(&cmdbuf[5],1);
1088         }
1089
1090         else if (!strncasecmp(cmdbuf,"KICK",4)) {
1091                 cmd_invt_kick(&cmdbuf[5],0);
1092         }
1093
1094         else if (!strncasecmp(cmdbuf,"GETR",4)) {
1095                 cmd_getr();
1096         }
1097
1098         else if (!strncasecmp(cmdbuf,"SETR",4)) {
1099                 cmd_setr(&cmdbuf[5]);
1100         }
1101
1102         else if (!strncasecmp(cmdbuf,"GETA",4)) {
1103                 cmd_geta();
1104         }
1105
1106         else if (!strncasecmp(cmdbuf,"SETA",4)) {
1107                 cmd_seta(&cmdbuf[5]);
1108         }
1109
1110         else if (!strncasecmp(cmdbuf,"ENT0",4)) {
1111                 cmd_ent0(&cmdbuf[5]);
1112         }
1113
1114         else if (!strncasecmp(cmdbuf,"RINF",4)) {
1115                 cmd_rinf();
1116         }
1117
1118         else if (!strncasecmp(cmdbuf,"DELE",4)) {
1119                 cmd_dele(&cmdbuf[5]);
1120         }
1121
1122         else if (!strncasecmp(cmdbuf,"KILL",4)) {
1123                 cmd_kill(&cmdbuf[5]);
1124         }
1125
1126         else if (!strncasecmp(cmdbuf,"CRE8",4)) {
1127                 cmd_cre8(&cmdbuf[5]);
1128         }
1129
1130         else if (!strncasecmp(cmdbuf,"MOVE",4)) {
1131                 cmd_move(&cmdbuf[5]);
1132         }
1133
1134         else if (!strncasecmp(cmdbuf,"FORG",4)) {
1135                 cmd_forg();
1136         }
1137
1138         else if (!strncasecmp(cmdbuf,"MESG",4)) {
1139                 cmd_mesg(&cmdbuf[5]);
1140         }
1141
1142         else if (!strncasecmp(cmdbuf,"EMSG",4)) {
1143                 cmd_emsg(&cmdbuf[5]);
1144         }
1145
1146         else if (!strncasecmp(cmdbuf,"GNUR",4)) {
1147                 cmd_gnur();
1148         }
1149
1150         else if (!strncasecmp(cmdbuf,"VALI",4)) {
1151                 cmd_vali(&cmdbuf[5]);
1152         }
1153
1154         else if (!strncasecmp(cmdbuf,"EINF",4)) {
1155                 cmd_einf(&cmdbuf[5]);
1156         }
1157
1158         else if (!strncasecmp(cmdbuf,"LIST",4)) {
1159                 cmd_list(&cmdbuf[5]);
1160         }
1161
1162         else if (!strncasecmp(cmdbuf,"CHEK",4)) {
1163                 cmd_chek();
1164         }
1165
1166         else if (!strncasecmp(cmdbuf,"DELF",4)) {
1167                 cmd_delf(&cmdbuf[5]);
1168         }
1169
1170         else if (!strncasecmp(cmdbuf,"MOVF",4)) {
1171                 cmd_movf(&cmdbuf[5]);
1172         }
1173
1174         else if (!strncasecmp(cmdbuf,"NETF",4)) {
1175                 cmd_netf(&cmdbuf[5]);
1176         }
1177
1178         else if (!strncasecmp(cmdbuf,"OPEN",4)) {
1179                 cmd_open(&cmdbuf[5]);
1180         }
1181
1182         else if (!strncasecmp(cmdbuf,"CLOS",4)) {
1183                 cmd_clos();
1184         }
1185
1186         else if (!strncasecmp(cmdbuf,"UOPN",4)) {
1187                 cmd_uopn(&cmdbuf[5]);
1188         }
1189
1190         else if (!strncasecmp(cmdbuf,"UCLS",4)) {
1191                 cmd_ucls(&cmdbuf[5]);
1192         }
1193
1194         else if (!strncasecmp(cmdbuf,"READ",4)) {
1195                 cmd_read(&cmdbuf[5]);
1196         }
1197
1198         else if (!strncasecmp(cmdbuf,"WRIT",4)) {
1199                 cmd_writ(&cmdbuf[5]);
1200         }
1201
1202         else if (!strncasecmp(cmdbuf,"QUSR",4)) {
1203                 cmd_qusr(&cmdbuf[5]);
1204         }
1205
1206         else if (!strncasecmp(cmdbuf,"ECHO",4)) {
1207                 cmd_echo(&cmdbuf[5]);
1208         }
1209
1210         else if (!strncasecmp(cmdbuf,"OIMG",4)) {
1211                 cmd_oimg(&cmdbuf[5]);
1212         }
1213
1214         else if (!strncasecmp(cmdbuf,"MORE",4)) {
1215                 cmd_more();
1216         }
1217
1218         else if (!strncasecmp(cmdbuf,"NDOP",4)) {
1219                 cmd_ndop(&cmdbuf[5]);
1220         }
1221
1222         else if (!strncasecmp(cmdbuf,"NUOP",4)) {
1223                 cmd_nuop(&cmdbuf[5]);
1224         }
1225
1226         else if (!strncasecmp(cmdbuf,"LFLR",4)) {
1227                 cmd_lflr();
1228         }
1229
1230         else if (!strncasecmp(cmdbuf,"CFLR",4)) {
1231                 cmd_cflr(&cmdbuf[5]);
1232         }
1233
1234         else if (!strncasecmp(cmdbuf,"KFLR",4)) {
1235                 cmd_kflr(&cmdbuf[5]);
1236         }
1237
1238         else if (!strncasecmp(cmdbuf,"EFLR",4)) {
1239                 cmd_eflr(&cmdbuf[5]);
1240         }
1241
1242         else if (!strncasecmp(cmdbuf,"IDEN",4)) {
1243                 cmd_iden(&cmdbuf[5]);
1244         }
1245
1246         else if (!strncasecmp(cmdbuf,"IPGM",4)) {
1247                 cmd_ipgm(&cmdbuf[5]);
1248         }
1249
1250         else if (!strncasecmp(cmdbuf,"TERM",4)) {
1251                 cmd_term(&cmdbuf[5]);
1252         }
1253
1254         else if (!strncasecmp(cmdbuf,"DOWN",4)) {
1255                 cmd_down();
1256         }
1257
1258         else if (!strncasecmp(cmdbuf,"HALT",4)) {
1259                 cmd_halt();
1260         }
1261
1262         else if (!strncasecmp(cmdbuf,"SCDN",4)) {
1263                 cmd_scdn(&cmdbuf[5]);
1264         }
1265
1266         else if (!strncasecmp(cmdbuf, "UIMG", 4)) {
1267                 cmd_uimg(&cmdbuf[5]);
1268         }
1269
1270         else if (!strncasecmp(cmdbuf, "TIME", 4)) {
1271                 cmd_time();
1272         }
1273
1274         else if (!strncasecmp(cmdbuf, "AGUP", 4)) {
1275                 cmd_agup(&cmdbuf[5]);
1276         }
1277
1278         else if (!strncasecmp(cmdbuf, "ASUP", 4)) {
1279                 cmd_asup(&cmdbuf[5]);
1280         }
1281
1282         else if (!strncasecmp(cmdbuf, "GPEX", 4)) {
1283                 cmd_gpex(&cmdbuf[5]);
1284         }
1285
1286         else if (!strncasecmp(cmdbuf, "SPEX", 4)) {
1287                 cmd_spex(&cmdbuf[5]);
1288         }
1289
1290         else if (!strncasecmp(cmdbuf, "CONF", 4)) {
1291                 cmd_conf(&cmdbuf[5]);
1292         }
1293
1294         else if (!strncasecmp(cmdbuf, "SEEN", 4)) {
1295                 cmd_seen(&cmdbuf[5]);
1296         }
1297
1298         else if (!strncasecmp(cmdbuf, "GTSN", 4)) {
1299                 cmd_gtsn(&cmdbuf[5]);
1300         }
1301
1302         else if (!strncasecmp(cmdbuf, "VIEW", 4)) {
1303                 cmd_view(&cmdbuf[5]);
1304         }
1305
1306         else if (!strncasecmp(cmdbuf, "ISME", 4)) {
1307                 cmd_isme(&cmdbuf[5]);
1308         }
1309
1310         else if (!DLoader_Exec_Cmd(cmdbuf)) {
1311                 cprintf("%d Unrecognized or unsupported command.\n",
1312                         ERROR + CMD_NOT_SUPPORTED);
1313                }
1314
1315         unbuffer_output();
1316
1317         /* Run any after-each-command routines registered by modules */
1318         PerformSessionHooks(EVT_CMD);
1319 }
1320
1321
1322 /*
1323  * This loop performs all asynchronous functions.
1324  */
1325 void do_async_loop(void) {
1326         PerformSessionHooks(EVT_ASYNC);
1327 }