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 <dlfcn.h> */
  35 #include <netdb.h>
  36 #include <sys/types.h>
  37 #include <sys/socket.h>
  38 #include <netinet/in.h>
  39 #include <arpa/inet.h>
  40 #include "citadel.h"
  41 #include "server.h"
  42 #include "serv_extensions.h"
  43 #include "sysdep_decls.h"
  44 #include "citserver.h"
  45 #include "config.h"
  46 #include "database.h"
  47 #include "housekeeping.h"
  48 #include "user_ops.h"
  49 #include "msgbase.h"
  50 #include "support.h"
  51 #include "locate_host.h"
  52 #include "room_ops.h"
  53 #include "file_ops.h"
  54 #include "policy.h"
  55 #include "control.h"
  56 #include "tools.h"
  57 #include "euidindex.h"
  58
  59 #ifndef HAVE_SNPRINTF
  60 #include "snprintf.h"
  61 #endif
  62
  63 struct CitContext *ContextList = NULL;
  64 struct CitContext* next_session = NULL;
  65 char *unique_session_numbers;
  66 int ScheduledShutdown = 0;
  67 int do_defrag = 0;
  68 time_t server_startup_time;
  69 char pid_file_name[PATH_MAX];
  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         FILE *pidfile_fp;
  80
  81         lprintf(CTDL_DEBUG, "master_startup() started\n");
  82         time(&server_startup_time);
  83
  84         /* pid file.  If we go FSSTND this should end up in 'localstatedir' */
  85         snprintf(pid_file_name, sizeof pid_file_name, "./citadel.pid");
  86         pidfile_fp = fopen(pid_file_name, "w");
  87         if (pidfile_fp != NULL) {
  88                 fprintf(pidfile_fp, "%d\n", (int)getpid());
  89                 fclose(pidfile_fp);
  90         }
  91
  92         lprintf(CTDL_INFO, "Opening databases\n");
  93         open_databases();
  94
  95         if (do_defrag) {
  96                 defrag_databases();
  97         }
  98
  99         check_ref_counts();
 100
 101         lprintf(CTDL_INFO, "Creating base rooms (if necessary)\n");
 102         create_room(config.c_baseroom,  0, "", 0, 1, 0, VIEW_BBS);
 103         create_room(AIDEROOM,           3, "", 0, 1, 0, VIEW_BBS);
 104         create_room(SYSCONFIGROOM,      3, "", 0, 1, 0, VIEW_BBS);
 105         create_room(config.c_twitroom,  0, "", 0, 1, 0, VIEW_BBS);
 106
 107         /* The "Local System Configuration" room doesn't need to be visible */
 108         if (lgetroom(&qrbuf, SYSCONFIGROOM) == 0) {
 109                 qrbuf.QRflags2 |= QR2_SYSTEM;
 110                 lputroom(&qrbuf);
 111         }
 112
 113         /*
 114          * Create a room in which we can deposit "deleted" messages for
 115          * deferred deletion.  This will silently fail if the room already
 116          * exists, and that's perfectly ok, because we want it to exist.
 117          */
 118         create_room(DELETED_MSGS_ROOM, 3, "", 0, 1, 0, VIEW_MAILBOX);
 119
 120         /*
 121          * Make sure it's set to be a "system room" so it doesn't show up
 122          * in the <K>nown rooms list for Aides.  Also set the message expire
 123          * policy to "by count, 1 message" so everything gets deleted all
 124          * the time (we can't set it to 0 because that's invalid, so we keep
 125          * a single message around).
 126          */
 127         if (lgetroom(&qrbuf, DELETED_MSGS_ROOM) == 0) {
 128                 qrbuf.QRflags2 |= QR2_SYSTEM;
 129                 qrbuf.QRep.expire_mode = EXPIRE_NUMMSGS;
 130                 qrbuf.QRep.expire_value = 1;
 131                 lputroom(&qrbuf);
 132         }
 133
 134         lprintf(CTDL_INFO, "Seeding the pseudo-random number generator...\n");
 135         urandom = fopen("/dev/urandom", "r");
 136         if (urandom != NULL) {
 137                 fread(&seed, sizeof seed, 1, urandom);
 138                 fclose(urandom);
 139         }
 140         else {
 141                 gettimeofday(&tv, NULL);
 142                 seed = tv.tv_usec;
 143         }
 144         srandom(seed);
 145
 146         lprintf(CTDL_INFO, "Initializing ipgm secret\n");
 147         get_config();
 148         config.c_ipgm_secret = rand();
 149         put_config();
 150
 151         lprintf(CTDL_DEBUG, "master_startup() finished\n");
 152 }
 153
 154
 155 /*
 156  * Cleanup routine to be called when the server is shutting down.
 157  */
 158 void master_cleanup(int exitcode) {
 159         struct CleanupFunctionHook *fcn;
 160         static int already_cleaning_up = 0;
 161
 162         if (already_cleaning_up) while(1) sleep(1);
 163         already_cleaning_up = 1;
 164
 165         /* Run any cleanup routines registered by loadable modules */
 166         for (fcn = CleanupHookTable; fcn != NULL; fcn = fcn->next) {
 167                 (*fcn->h_function_pointer)();
 168         }
 169
 170         /* Shut down the indexer thread */
 171         lprintf(CTDL_INFO, "Waiting for the indexer thread to shut down\n");
 172         pthread_join(indexer_thread_tid, NULL);
 173
 174         /* Shut down the checkpoint thread */
 175         lprintf(CTDL_INFO, "Waiting for the checkpoint thread to shut down\n");
 176         pthread_join(checkpoint_thread_tid, NULL);
 177
 178         /* Close databases */
 179         lprintf(CTDL_INFO, "Closing databases\n");
 180         close_databases();
 181
 182         /* Do system-dependent stuff */
 183         sysdep_master_cleanup();
 184
 185 #ifdef DEBUG_MEMORY_LEAKS
 186         dump_heap();
 187 #endif
 188
 189         /* Now go away. */
 190         lprintf(CTDL_NOTICE, "citserver: Exiting with status %d\n", exitcode);
 191         fflush(stdout); fflush(stderr);
 192
 193         unlink(pid_file_name);
 194         exit(exitcode);
 195 }
 196
 197
 198
 199 /*
 200  * Terminate a session.
 201  */
 202 void RemoveContext (struct CitContext *con)
 203 {
 204         if (con==NULL) {
 205                 lprintf(CTDL_ERR,
 206                         "WARNING: RemoveContext() called with NULL!\n");
 207                 return;
 208         }
 209         lprintf(CTDL_DEBUG, "RemoveContext() session %d\n", con->cs_pid);
 210
 211         /* Run any cleanup routines registered by loadable modules.
 212          * Note: We have to "become_session()" because the cleanup functions
 213          *       might make references to "CC" assuming it's the right one.
 214          */
 215         become_session(con);
 216         PerformSessionHooks(EVT_STOP);
 217         become_session(NULL);
 218
 219         /* Now handle all of the administrivia. */
 220         lprintf(CTDL_DEBUG, "Calling logout(%d)\n", con->cs_pid);
 221         logout(con);
 222
 223         lprintf(CTDL_NOTICE, "[%3d] Session ended.\n", con->cs_pid);
 224
 225         /* If the client is still connected, blow 'em away. */
 226         lprintf(CTDL_DEBUG, "Closing socket %d\n", con->client_socket);
 227         close(con->client_socket);
 228
 229         lprintf(CTDL_DEBUG, "Done with RemoveContext()\n");
 230 }
 231
 232
 233
 234
 235
 236 /*
 237  * cmd_info()  -  tell the client about this server
 238  */
 239 void cmd_info(void) {
 240         cprintf("%d Server info:\n", LISTING_FOLLOWS);
 241         cprintf("%d\n", CC->cs_pid);
 242         cprintf("%s\n", config.c_nodename);
 243         cprintf("%s\n", config.c_humannode);
 244         cprintf("%s\n", config.c_fqdn);
 245         cprintf("%s\n", CITADEL);
 246         cprintf("%d\n", REV_LEVEL);
 247         cprintf("%s\n", config.c_site_location);
 248         cprintf("%s\n", config.c_sysadm);
 249         cprintf("%d\n", SERVER_TYPE);
 250         cprintf("%s\n", config.c_moreprompt);
 251         cprintf("1\n"); /* 1 = yes, this system supports floors */
 252         cprintf("1\n"); /* 1 = we support the extended paging options */
 253         cprintf("%s\n", CC->cs_nonce);
 254         cprintf("1\n"); /* 1 = yes, this system supports the QNOP command */
 255 #ifdef HAVE_LDAP
 256         cprintf("1\n"); /* 1 = yes, this server is LDAP-enabled */
 257 #else
 258         cprintf("0\n"); /* 1 = no, this server is not LDAP-enabled */
 259 #endif
 260         cprintf("000\n");
 261 }
 262
 263
 264 /*
 265  * returns an asterisk if there are any instant messages waiting,
 266  * space otherwise.
 267  */
 268 char CtdlCheckExpress(void) {
 269         if (CC->FirstExpressMessage == NULL) {
 270                 return(' ');
 271         }
 272         else {
 273                 return('*');
 274         }
 275 }
 276
 277 void cmd_time(void)
 278 {
 279    time_t tv;
 280    struct tm tmp;
 281
 282    tv = time(NULL);
 283    localtime_r(&tv, &tmp);
 284
 285    /* timezone and daylight global variables are not portable. */
 286 #ifdef HAVE_STRUCT_TM_TM_GMTOFF
 287    cprintf("%d %ld|%ld|%d\n", CIT_OK, (long)tv, tmp.tm_gmtoff, tmp.tm_isdst);
 288 #else
 289    cprintf("%d %ld|%ld|%d\n", CIT_OK, (long)tv, timezone, tmp.tm_isdst);
 290 #endif
 291 }
 292
 293
 294 /*
 295  * Check originating host against the public_clients file.  This determines
 296  * whether the client is allowed to change the hostname for this session
 297  * (for example, to show the location of the user rather than the location
 298  * of the client).
 299  */
 300 int is_public_client(void)
 301 {
 302         char buf[1024];
 303         char addrbuf[1024];
 304         FILE *fp;
 305         int i;
 306         struct stat statbuf;
 307         static time_t pc_timestamp = 0;
 308         static char public_clients[SIZ];
 309
 310 #ifndef HAVE_ETC
 311 #define PUBLIC_CLIENTS "./public_clients"
 312 #else
 313 #define PUBLIC_CLIENTS ETC_DIR"/public_clients"
 314 #endif
 315
 316         /*
 317          * Check the time stamp on the public_clients file.  If it's been
 318          * updated since the last time we were here (or if this is the first
 319          * time we've been through the loop), read its contents and learn
 320          * the IP addresses of the listed hosts.
 321          */
 322         if (stat(PUBLIC_CLIENTS, &statbuf) != 0) {
 323                 /* No public_clients file exists, so bail out */
 324                 lprintf(CTDL_WARNING, "Warning: '%s' does not exist\n", PUBLIC_CLIENTS);
 325                 return(0);
 326         }
 327
 328         if (statbuf.st_mtime > pc_timestamp) {
 329                 begin_critical_section(S_PUBLIC_CLIENTS);
 330                 lprintf(CTDL_INFO, "Loading %s\n", PUBLIC_CLIENTS);
 331
 332                 safestrncpy(public_clients, "127.0.0.1", sizeof public_clients);
 333                 if (hostname_to_dotted_quad(addrbuf, config.c_fqdn) == 0) {
 334                         strcat(public_clients, "|");
 335                         strcat(public_clients, addrbuf);
 336                 }
 337
 338                 fp = fopen(
 339 #ifndef HAVE_ETC
 340                                    "."
 341 #else
 342                                    ETC_DIR
 343 #endif
 344                                    "/public_clients", "r");
 345                 if (fp != NULL) while (fgets(buf, sizeof buf, fp)!=NULL) {
 346                         for (i=0; i<strlen(buf); ++i) {
 347                                 if (buf[i] == '#') buf[i] = 0;
 348                         }
 349                         while (isspace((buf[strlen(buf)-1]))) {
 350                                 buf[strlen(buf)-1] = 0;
 351                         }
 352                         if (hostname_to_dotted_quad(addrbuf, buf) == 0) {
 353                                 if ((strlen(public_clients) +
 354                                    strlen(addrbuf) + 2)
 355                                    < sizeof(public_clients)) {
 356                                         strcat(public_clients, addrbuf);
 357                                 }
 358                         }
 359                 }
 360                 fclose(fp);
 361                 pc_timestamp = time(NULL);
 362                 end_critical_section(S_PUBLIC_CLIENTS);
 363         }
 364
 365         lprintf(CTDL_DEBUG, "Checking whether %s is a local or public client\n",
 366                 CC->cs_addr);
 367         for (i=0; i<num_parms(public_clients); ++i) {
 368                 extract_token(addrbuf, public_clients, i, '|', sizeof addrbuf);
 369                 if (!strcasecmp(CC->cs_addr, addrbuf)) {
 370                         lprintf(CTDL_DEBUG, "... yes it is.\n");
 371                         return(1);
 372                 }
 373         }
 374
 375         /* No hits.  This is not a public client. */
 376         lprintf(CTDL_DEBUG, "... no it isn't.\n");
 377         return(0);
 378 }
 379
 380
 381 /*
 382  * the client is identifying itself to the server
 383  */
 384 void cmd_iden(char *argbuf)
 385 {
 386         int dev_code;
 387         int cli_code;
 388         int rev_level;
 389         char desc[128];
 390         char from_host[128];
 391         struct in_addr addr;
 392         int do_lookup = 0;
 393
 394         if (num_parms(argbuf)<4) {
 395                 cprintf("%d usage error\n", ERROR + ILLEGAL_VALUE);
 396                 return;
 397         }
 398
 399         dev_code = extract_int(argbuf,0);
 400         cli_code = extract_int(argbuf,1);
 401         rev_level = extract_int(argbuf,2);
 402         extract_token(desc, argbuf, 3, '|', sizeof desc);
 403
 404         safestrncpy(from_host, config.c_fqdn, sizeof from_host);
 405         from_host[sizeof from_host - 1] = 0;
 406         if (num_parms(argbuf)>=5) extract_token(from_host, argbuf, 4, '|', sizeof from_host);
 407
 408         CC->cs_clientdev = dev_code;
 409         CC->cs_clienttyp = cli_code;
 410         CC->cs_clientver = rev_level;
 411         safestrncpy(CC->cs_clientname, desc, sizeof CC->cs_clientname);
 412         CC->cs_clientname[31] = 0;
 413
 414         if (strlen(from_host) > 0) {
 415                 if (CC->is_local_socket) do_lookup = 1;
 416                 else if (is_public_client()) do_lookup = 1;
 417         }
 418
 419         if (do_lookup) {
 420                 lprintf(CTDL_DEBUG, "Looking up hostname '%s'\n", from_host);
 421                 if ((addr.s_addr = inet_addr(from_host)) != -1) {
 422                         locate_host(CC->cs_host, sizeof CC->cs_host,
 423                                 NULL, 0,
 424                                 &addr);
 425                 }
 426                 else {
 427                         safestrncpy(CC->cs_host, from_host, sizeof CC->cs_host);
 428                         CC->cs_host[sizeof CC->cs_host - 1] = 0;
 429                 }
 430         }
 431
 432         lprintf(CTDL_NOTICE, "Client %d/%d/%01d.%02d (%s) from %s\n",
 433                 dev_code,
 434                 cli_code,
 435                 (rev_level / 100),
 436                 (rev_level % 100),
 437                 desc,
 438                 CC->cs_host);
 439         cprintf("%d Ok\n",CIT_OK);
 440 }
 441
 442
 443 /*
 444  * display system messages or help
 445  */
 446 void cmd_mesg(char *mname)
 447 {
 448         FILE *mfp;
 449         char targ[256];
 450         char buf[256];
 451         char buf2[256];
 452         char *dirs[2];
 453         DIR *dp;
 454         struct dirent *d;
 455
 456         extract_token(buf, mname, 0, '|', sizeof buf);
 457
 458 #ifdef HAVE_DATA_DIR
 459         dirs[0] = strdup(DATA_DIR "/messages");
 460 #else
 461         dirs[0] = strdup("messages");
 462 #endif
 463
 464 #ifdef HAVE_DATA_DIR
 465         dirs[1] = strdup(DATA_DIR "/help");
 466 #else
 467         dirs[1] = strdup("help");
 468 #endif
 469
 470         snprintf(buf2, sizeof buf2, "%s.%d.%d",
 471                 buf, CC->cs_clientdev, CC->cs_clienttyp);
 472
 473         /* If the client requested "?" then produce a listing */
 474         if (!strcmp(buf, "?")) {
 475                 cprintf("%d %s\n",LISTING_FOLLOWS,buf);
 476                 dp = opendir(dirs[1]);
 477                 if (dp != NULL) {
 478                         while (d = readdir(dp), d != NULL) {
 479                                 if (d->d_name[0] != '.') {
 480                                         cprintf(" %s\n", d->d_name);
 481                                 }
 482                         }
 483                         closedir(dp);
 484                 }
 485                 cprintf("000\n");
 486         }
 487
 488         /* Otherwise, look for the requested file by name. */
 489         else {
 490                 mesg_locate(targ, sizeof targ, buf2, 2, (const char **)dirs);
 491                 if (strlen(targ) == 0) {
 492                         snprintf(buf2, sizeof buf2, "%s.%d",
 493                                                         buf, CC->cs_clientdev);
 494                         mesg_locate(targ, sizeof targ, buf2, 2,
 495                                                         (const char **)dirs);
 496                         if (strlen(targ) == 0) {
 497                                 mesg_locate(targ, sizeof targ, buf, 2,
 498                                                         (const char **)dirs);
 499                         }
 500                 }
 501         }
 502
 503         free(dirs[0]);
 504         free(dirs[1]);
 505
 506         if (strlen(targ)==0) {
 507                 cprintf("%d '%s' not found.\n",ERROR + FILE_NOT_FOUND, mname);
 508                 return;
 509         }
 510
 511         mfp = fopen(targ,"r");
 512         if (mfp==NULL) {
 513                 cprintf("%d Cannot open '%s': %s\n",
 514                         ERROR + INTERNAL_ERROR, targ, strerror(errno));
 515                 return;
 516         }
 517         cprintf("%d %s\n",LISTING_FOLLOWS,buf);
 518
 519         while (fgets(buf, (sizeof buf - 1), mfp) != NULL) {
 520                 buf[strlen(buf)-1] = 0;
 521                 do_help_subst(buf);
 522                 cprintf("%s\n",buf);
 523         }
 524
 525         fclose(mfp);
 526         cprintf("000\n");
 527 }
 528
 529
 530 /*
 531  * enter system messages or help
 532  */
 533 void cmd_emsg(char *mname)
 534 {
 535         FILE *mfp;
 536         char targ[256];
 537         char buf[256];
 538         char *dirs[2];
 539         int a;
 540
 541         unbuffer_output();
 542
 543         if (CtdlAccessCheck(ac_aide)) return;
 544
 545         extract_token(buf, mname, 0, '|', sizeof buf);
 546         for (a=0; a<strlen(buf); ++a) {         /* security measure */
 547                 if (buf[a] == '/') buf[a] = '.';
 548         }
 549
 550 #ifdef HAVE_DATA_DIR
 551         dirs[0] = strdup(DATA_DIR "/messages");
 552 #else
 553         dirs[0] = strdup("messages");
 554 #endif
 555
 556 #ifdef HAVE_DATA_DIR
 557         dirs[1] = strdup(DATA_DIR "/help");
 558 #else
 559         dirs[1] = strdup("help");
 560 #endif
 561
 562         mesg_locate(targ, sizeof targ, buf, 2, (const char**)dirs);
 563         free(dirs[0]);
 564         free(dirs[1]);
 565
 566         if (strlen(targ)==0) {
 567                 snprintf(targ, sizeof targ,
 568 #ifndef HAVE_DATA_DIR
 569                          "."
 570 #else
 571                          DATA_DIR
 572 #endif
 573                                  "/help/%s", buf);
 574         }
 575
 576         mfp = fopen(targ,"w");
 577         if (mfp==NULL) {
 578                 cprintf("%d Cannot open '%s': %s\n",
 579                         ERROR + INTERNAL_ERROR, targ, strerror(errno));
 580                 return;
 581         }
 582         cprintf("%d %s\n", SEND_LISTING, targ);
 583
 584         while (client_getln(buf, sizeof buf), strcmp(buf, "000")) {
 585                 fprintf(mfp, "%s\n", buf);
 586         }
 587
 588         fclose(mfp);
 589 }
 590
 591
 592 /* Don't show the names of private rooms unless the viewing
 593  * user also knows the rooms.
 594  */
 595 void GenerateRoomDisplay(char *real_room,
 596                         struct CitContext *viewed,
 597                         struct CitContext *viewer) {
 598
 599         int ra;
 600
 601         strcpy(real_room, viewed->room.QRname);
 602         if (viewed->room.QRflags & QR_MAILBOX) {
 603                 strcpy(real_room, &real_room[11]);
 604         }
 605         if (viewed->room.QRflags & QR_PRIVATE) {
 606                 CtdlRoomAccess(&viewed->room, &viewer->user, &ra, NULL);
 607                 if ( (ra & UA_KNOWN) == 0) {
 608                         strcpy(real_room, "<private room>");
 609                 }
 610         }
 611
 612         if (viewed->cs_flags & CS_CHAT) {
 613                 while (strlen(real_room) < 14)
 614                         strcat(real_room, " ");
 615
 616                 strcpy(&real_room[14], "<chat>");
 617         }
 618
 619 }
 620
 621 /*
 622  * Convenience function.
 623  */
 624 int CtdlAccessCheck(int required_level) {
 625
 626         if (CC->internal_pgm) return(0);
 627         if (required_level >= ac_internal) {
 628                 cprintf("%d This is not a user-level command.\n",
 629                         ERROR + HIGHER_ACCESS_REQUIRED);
 630                 return(-1);
 631         }
 632
 633         if ((required_level >= ac_logged_in) && (CC->logged_in == 0)) {
 634                 cprintf("%d Not logged in.\n", ERROR + NOT_LOGGED_IN);
 635                 return(-1);
 636         }
 637
 638         if (CC->user.axlevel >= 6) return(0);
 639         if (required_level >= ac_aide) {
 640                 cprintf("%d This command requires Aide access.\n",
 641                         ERROR + HIGHER_ACCESS_REQUIRED);
 642                 return(-1);
 643         }
 644
 645         if (is_room_aide()) return(0);
 646         if (required_level >= ac_room_aide) {
 647                 cprintf("%d This command requires Aide or Room Aide access.\n",
 648                         ERROR + HIGHER_ACCESS_REQUIRED);
 649                 return(-1);
 650         }
 651
 652         /* shhh ... succeed quietly */
 653         return(0);
 654 }
 655
 656
 657
 658 /*
 659  * Terminate another running session
 660  */
 661 void cmd_term(char *cmdbuf)
 662 {
 663         int session_num;
 664         struct CitContext *ccptr;
 665         int found_it = 0;
 666         int allowed = 0;
 667
 668         session_num = extract_int(cmdbuf, 0);
 669         if (session_num == CC->cs_pid) {
 670                 cprintf("%d You can't kill your own session.\n", ERROR + ILLEGAL_VALUE);
 671                 return;
 672         }
 673
 674         lprintf(CTDL_DEBUG, "Locating session to kill\n");
 675         begin_critical_section(S_SESSION_TABLE);
 676         for (ccptr = ContextList; ccptr != NULL; ccptr = ccptr->next) {
 677                 if (session_num == ccptr->cs_pid) {
 678                         found_it = 1;
 679                         if ((ccptr->user.usernum == CC->user.usernum)
 680                            || (CC->user.axlevel >= 6)) {
 681                                 allowed = 1;
 682                                 ccptr->kill_me = 1;
 683                         }
 684                         else {
 685                                 allowed = 0;
 686                         }
 687                 }
 688         }
 689         end_critical_section(S_SESSION_TABLE);
 690
 691         if (found_it) {
 692                 if (allowed) {
 693                         cprintf("%d Session terminated.\n", CIT_OK);
 694                 }
 695                 else {
 696                         cprintf("%d You are not allowed to do that.\n",
 697                                 ERROR + HIGHER_ACCESS_REQUIRED);
 698                 }
 699         }
 700         else {
 701                 cprintf("%d No such session.\n", ERROR + ILLEGAL_VALUE);
 702         }
 703 }
 704
 705
 706
 707
 708
 709 /*
 710  * get the paginator prompt
 711  */
 712 void cmd_more(void) {
 713         cprintf("%d %s\n", CIT_OK, config.c_moreprompt);
 714 }
 715
 716 /*
 717  * echo
 718  */
 719 void cmd_echo(char *etext)
 720 {
 721         cprintf("%d %s\n", CIT_OK, etext);
 722 }
 723
 724
 725
 726 /*
 727  * identify as internal program
 728  */
 729 void cmd_ipgm(char *argbuf)
 730 {
 731         int secret;
 732
 733         secret = extract_int(argbuf, 0);
 734
 735         /* For security reasons, we do NOT allow this command to run
 736          * over the network.  Local sockets only.
 737          */
 738         if (!CC->is_local_socket) {
 739                 sleep(5);
 740                 cprintf("%d Authentication failed.\n",
 741                         ERROR + PASSWORD_REQUIRED);
 742         }
 743         else if (secret == config.c_ipgm_secret) {
 744                 CC->internal_pgm = 1;
 745                 strcpy(CC->curr_user, "<internal program>");
 746                 CC->cs_flags = CC->cs_flags|CS_STEALTH;
 747                 cprintf("%d Authenticated as an internal program.\n", CIT_OK);
 748         }
 749         else {
 750                 sleep(5);
 751                 cprintf("%d Authentication failed.\n",
 752                         ERROR + PASSWORD_REQUIRED);
 753                 lprintf(CTDL_ERR, "Warning: ipgm authentication failed.\n");
 754                 CC->kill_me = 1;
 755         }
 756
 757         /* Now change the ipgm secret for the next round.
 758          * (Disabled because it breaks concurrent scripts.  The fact that
 759          * we no longer accept IPGM over the network should be sufficient
 760          * to prevent brute-force attacks.  If you don't agree, uncomment
 761          * this block.)
 762         get_config();
 763         config.c_ipgm_secret = rand();
 764         put_config();
 765         */
 766 }
 767
 768
 769 /*
 770  * Shut down the server
 771  */
 772 void cmd_down(void) {
 773
 774         if (CtdlAccessCheck(ac_aide)) return;
 775
 776         cprintf("%d Shutting down server.  Goodbye.\n", CIT_OK);
 777         time_to_die = 1;
 778 }
 779
 780 /*
 781  * Schedule or cancel a server shutdown
 782  */
 783 void cmd_scdn(char *argbuf)
 784 {
 785         int new_state;
 786
 787         if (CtdlAccessCheck(ac_aide)) return;
 788
 789         new_state = extract_int(argbuf, 0);
 790         if ((new_state == 0) || (new_state == 1)) {
 791                 ScheduledShutdown = new_state;
 792         }
 793         cprintf("%d %d\n", CIT_OK, ScheduledShutdown);
 794 }
 795
 796
 797 /*
 798  * Set or unset asynchronous protocol mode
 799  */
 800 void cmd_asyn(char *argbuf)
 801 {
 802         int new_state;
 803
 804         new_state = extract_int(argbuf, 0);
 805         if ((new_state == 0) || (new_state == 1)) {
 806                 CC->is_async = new_state;
 807         }
 808         cprintf("%d %d\n", CIT_OK, CC->is_async);
 809 }
 810
 811
 812 /*
 813  * Generate a "nonce" for APOP-style authentication.
 814  *
 815  * RFC 1725 et al specify a PID to be placed in front of the nonce.
 816  * Quoth BTX: That would be stupid.
 817  */
 818 void generate_nonce(struct CitContext *con) {
 819         struct timeval tv;
 820
 821         memset(con->cs_nonce, NONCE_SIZE, 0);
 822         gettimeofday(&tv, NULL);
 823         memset(con->cs_nonce, NONCE_SIZE, 0);
 824         snprintf(con->cs_nonce, NONCE_SIZE, "<%d%ld@%s>",
 825                 rand(), (long)tv.tv_usec, config.c_fqdn);
 826 }
 827
 828
 829
 830
 831 /*
 832  * Back-end function for starting a session
 833  */
 834 void begin_session(struct CitContext *con)
 835 {
 836         int len;
 837         struct sockaddr_in sin;
 838
 839         /*
 840          * Initialize some variables specific to our context.
 841          */
 842         con->logged_in = 0;
 843         con->internal_pgm = 0;
 844         con->download_fp = NULL;
 845         con->upload_fp = NULL;
 846         con->FirstExpressMessage = NULL;
 847         time(&con->lastcmd);
 848         time(&con->lastidle);
 849         strcpy(con->lastcmdname, "    ");
 850         strcpy(con->cs_clientname, "(unknown)");
 851         strcpy(con->curr_user, NLI);
 852         strcpy(con->net_node, "");
 853         strcpy(con->fake_username, "");
 854         strcpy(con->fake_postname, "");
 855         strcpy(con->fake_hostname, "");
 856         strcpy(con->fake_roomname, "");
 857         generate_nonce(con);
 858         safestrncpy(con->cs_host, config.c_fqdn, sizeof con->cs_host);
 859         safestrncpy(con->cs_addr, "", sizeof con->cs_addr);
 860         con->cs_host[sizeof con->cs_host - 1] = 0;
 861         len = sizeof sin;
 862         if (!CC->is_local_socket) {
 863                 if (!getpeername(con->client_socket,
 864                    (struct sockaddr *) &sin, &len))     /* should be socklen_t but doesn't work on Macintosh */
 865                         locate_host(con->cs_host, sizeof con->cs_host,
 866                                 con->cs_addr, sizeof con->cs_addr,
 867                                 &sin.sin_addr);
 868         }
 869         else {
 870                 strcpy(con->cs_host, "");
 871         }
 872         con->cs_flags = 0;
 873         con->upload_type = UPL_FILE;
 874         con->dl_is_net = 0;
 875
 876         con->nologin = 0;
 877         if ((config.c_maxsessions > 0)&&(num_sessions > config.c_maxsessions))
 878                 con->nologin = 1;
 879
 880         lprintf(CTDL_NOTICE, "Session started.\n");
 881
 882         /* Run any session startup routines registered by loadable modules */
 883         PerformSessionHooks(EVT_START);
 884 }
 885
 886
 887 void citproto_begin_session() {
 888         if (CC->nologin==1) {
 889                 cprintf("%d %s: Too many users are already online "
 890                         "(maximum is %d)\n",
 891                         ERROR + MAX_SESSIONS_EXCEEDED,
 892                         config.c_nodename, config.c_maxsessions);
 893         }
 894         else {
 895                 cprintf("%d %s Citadel server ready.\n",
 896                         CIT_OK, config.c_nodename);
 897         }
 898 }
 899
 900
 901
 902
 903 /*
 904  * This loop recognizes all server commands.
 905  */
 906 void do_command_loop(void) {
 907         char cmdbuf[SIZ];
 908
 909         time(&CC->lastcmd);
 910         memset(cmdbuf, 0, sizeof cmdbuf); /* Clear it, just in case */
 911         if (client_getln(cmdbuf, sizeof cmdbuf) < 1) {
 912                 lprintf(CTDL_ERR, "Client disconnected: ending session.\n");
 913                 CC->kill_me = 1;
 914                 return;
 915         }
 916
 917         /* Log the server command, but don't show passwords... */
 918         if ( (strncasecmp(cmdbuf, "PASS", 4))
 919            && (strncasecmp(cmdbuf, "SETP", 4)) ) {
 920                 lprintf(CTDL_INFO, "%s\n", cmdbuf);
 921         }
 922         else {
 923                 lprintf(CTDL_INFO, "<password command sent>\n");
 924         }
 925
 926         buffer_output();
 927
 928         /*
 929          * Let other clients see the last command we executed, and
 930          * update the idle time, but not NOOP, QNOP, PEXP, or GEXP.
 931          */
 932         if ( (strncasecmp(cmdbuf, "NOOP", 4))
 933            && (strncasecmp(cmdbuf, "QNOP", 4))
 934            && (strncasecmp(cmdbuf, "PEXP", 4))
 935            && (strncasecmp(cmdbuf, "GEXP", 4)) ) {
 936                 strcpy(CC->lastcmdname, "    ");
 937                 safestrncpy(CC->lastcmdname, cmdbuf, 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,"EUID",4)) {
1039                 cmd_euid(&cmdbuf[5]);
1040         }
1041
1042         else if (!strncasecmp(cmdbuf,"MSG0",4)) {
1043                 cmd_msg0(&cmdbuf[5]);
1044         }
1045
1046         else if (!strncasecmp(cmdbuf,"MSG2",4)) {
1047                 cmd_msg2(&cmdbuf[5]);
1048         }
1049
1050         else if (!strncasecmp(cmdbuf,"MSG3",4)) {
1051                 cmd_msg3(&cmdbuf[5]);
1052         }
1053
1054         else if (!strncasecmp(cmdbuf,"MSG4",4)) {
1055                 cmd_msg4(&cmdbuf[5]);
1056         }
1057
1058         else if (!strncasecmp(cmdbuf,"MSGP",4)) {
1059                 cmd_msgp(&cmdbuf[5]);
1060         }
1061
1062         else if (!strncasecmp(cmdbuf,"OPNA",4)) {
1063                 cmd_opna(&cmdbuf[5]);
1064         }
1065
1066         else if (!strncasecmp(cmdbuf,"INFO",4)) {
1067                 cmd_info();
1068         }
1069
1070         else if (!strncasecmp(cmdbuf,"SLRP",4)) {
1071                 cmd_slrp(&cmdbuf[5]);
1072         }
1073
1074         else if (!strncasecmp(cmdbuf,"INVT",4)) {
1075                 cmd_invt_kick(&cmdbuf[5],1);
1076         }
1077
1078         else if (!strncasecmp(cmdbuf,"KICK",4)) {
1079                 cmd_invt_kick(&cmdbuf[5],0);
1080         }
1081
1082         else if (!strncasecmp(cmdbuf,"GETR",4)) {
1083                 cmd_getr();
1084         }
1085
1086         else if (!strncasecmp(cmdbuf,"SETR",4)) {
1087                 cmd_setr(&cmdbuf[5]);
1088         }
1089
1090         else if (!strncasecmp(cmdbuf,"GETA",4)) {
1091                 cmd_geta();
1092         }
1093
1094         else if (!strncasecmp(cmdbuf,"SETA",4)) {
1095                 cmd_seta(&cmdbuf[5]);
1096         }
1097
1098         else if (!strncasecmp(cmdbuf,"ENT0",4)) {
1099                 cmd_ent0(&cmdbuf[5]);
1100         }
1101
1102         else if (!strncasecmp(cmdbuf,"RINF",4)) {
1103                 cmd_rinf();
1104         }
1105
1106         else if (!strncasecmp(cmdbuf,"DELE",4)) {
1107                 cmd_dele(&cmdbuf[5]);
1108         }
1109
1110         else if (!strncasecmp(cmdbuf,"KILL",4)) {
1111                 cmd_kill(&cmdbuf[5]);
1112         }
1113
1114         else if (!strncasecmp(cmdbuf,"CRE8",4)) {
1115                 cmd_cre8(&cmdbuf[5]);
1116         }
1117
1118         else if (!strncasecmp(cmdbuf,"MOVE",4)) {
1119                 cmd_move(&cmdbuf[5]);
1120         }
1121
1122         else if (!strncasecmp(cmdbuf,"FORG",4)) {
1123                 cmd_forg();
1124         }
1125
1126         else if (!strncasecmp(cmdbuf,"MESG",4)) {
1127                 cmd_mesg(&cmdbuf[5]);
1128         }
1129
1130         else if (!strncasecmp(cmdbuf,"EMSG",4)) {
1131                 cmd_emsg(&cmdbuf[5]);
1132         }
1133
1134         else if (!strncasecmp(cmdbuf,"GNUR",4)) {
1135                 cmd_gnur();
1136         }
1137
1138         else if (!strncasecmp(cmdbuf,"VALI",4)) {
1139                 cmd_vali(&cmdbuf[5]);
1140         }
1141
1142         else if (!strncasecmp(cmdbuf,"EINF",4)) {
1143                 cmd_einf(&cmdbuf[5]);
1144         }
1145
1146         else if (!strncasecmp(cmdbuf,"LIST",4)) {
1147                 cmd_list(&cmdbuf[5]);
1148         }
1149
1150         else if (!strncasecmp(cmdbuf,"CHEK",4)) {
1151                 cmd_chek();
1152         }
1153
1154         else if (!strncasecmp(cmdbuf,"DELF",4)) {
1155                 cmd_delf(&cmdbuf[5]);
1156         }
1157
1158         else if (!strncasecmp(cmdbuf,"MOVF",4)) {
1159                 cmd_movf(&cmdbuf[5]);
1160         }
1161
1162         else if (!strncasecmp(cmdbuf,"NETF",4)) {
1163                 cmd_netf(&cmdbuf[5]);
1164         }
1165
1166         else if (!strncasecmp(cmdbuf,"OPEN",4)) {
1167                 cmd_open(&cmdbuf[5]);
1168         }
1169
1170         else if (!strncasecmp(cmdbuf,"CLOS",4)) {
1171                 cmd_clos();
1172         }
1173
1174         else if (!strncasecmp(cmdbuf,"UOPN",4)) {
1175                 cmd_uopn(&cmdbuf[5]);
1176         }
1177
1178         else if (!strncasecmp(cmdbuf,"UCLS",4)) {
1179                 cmd_ucls(&cmdbuf[5]);
1180         }
1181
1182         else if (!strncasecmp(cmdbuf,"READ",4)) {
1183                 cmd_read(&cmdbuf[5]);
1184         }
1185
1186         else if (!strncasecmp(cmdbuf,"WRIT",4)) {
1187                 cmd_writ(&cmdbuf[5]);
1188         }
1189
1190         else if (!strncasecmp(cmdbuf,"QUSR",4)) {
1191                 cmd_qusr(&cmdbuf[5]);
1192         }
1193
1194         else if (!strncasecmp(cmdbuf,"ECHO",4)) {
1195                 cmd_echo(&cmdbuf[5]);
1196         }
1197
1198         else if (!strncasecmp(cmdbuf,"OIMG",4)) {
1199                 cmd_oimg(&cmdbuf[5]);
1200         }
1201
1202         else if (!strncasecmp(cmdbuf,"MORE",4)) {
1203                 cmd_more();
1204         }
1205
1206         else if (!strncasecmp(cmdbuf,"NDOP",4)) {
1207                 cmd_ndop(&cmdbuf[5]);
1208         }
1209
1210         else if (!strncasecmp(cmdbuf,"NUOP",4)) {
1211                 cmd_nuop(&cmdbuf[5]);
1212         }
1213
1214         else if (!strncasecmp(cmdbuf,"LFLR",4)) {
1215                 cmd_lflr();
1216         }
1217
1218         else if (!strncasecmp(cmdbuf,"CFLR",4)) {
1219                 cmd_cflr(&cmdbuf[5]);
1220         }
1221
1222         else if (!strncasecmp(cmdbuf,"KFLR",4)) {
1223                 cmd_kflr(&cmdbuf[5]);
1224         }
1225
1226         else if (!strncasecmp(cmdbuf,"EFLR",4)) {
1227                 cmd_eflr(&cmdbuf[5]);
1228         }
1229
1230         else if (!strncasecmp(cmdbuf,"IDEN",4)) {
1231                 cmd_iden(&cmdbuf[5]);
1232         }
1233
1234         else if (!strncasecmp(cmdbuf,"IPGM",4)) {
1235                 cmd_ipgm(&cmdbuf[5]);
1236         }
1237
1238         else if (!strncasecmp(cmdbuf,"TERM",4)) {
1239                 cmd_term(&cmdbuf[5]);
1240         }
1241
1242         else if (!strncasecmp(cmdbuf,"DOWN",4)) {
1243                 cmd_down();
1244         }
1245
1246         else if (!strncasecmp(cmdbuf,"SCDN",4)) {
1247                 cmd_scdn(&cmdbuf[5]);
1248         }
1249
1250         else if (!strncasecmp(cmdbuf, "UIMG", 4)) {
1251                 cmd_uimg(&cmdbuf[5]);
1252         }
1253
1254         else if (!strncasecmp(cmdbuf, "TIME", 4)) {
1255                 cmd_time();
1256         }
1257
1258         else if (!strncasecmp(cmdbuf, "AGUP", 4)) {
1259                 cmd_agup(&cmdbuf[5]);
1260         }
1261
1262         else if (!strncasecmp(cmdbuf, "ASUP", 4)) {
1263                 cmd_asup(&cmdbuf[5]);
1264         }
1265
1266         else if (!strncasecmp(cmdbuf, "GPEX", 4)) {
1267                 cmd_gpex(&cmdbuf[5]);
1268         }
1269
1270         else if (!strncasecmp(cmdbuf, "SPEX", 4)) {
1271                 cmd_spex(&cmdbuf[5]);
1272         }
1273
1274         else if (!strncasecmp(cmdbuf, "CONF", 4)) {
1275                 cmd_conf(&cmdbuf[5]);
1276         }
1277
1278         else if (!strncasecmp(cmdbuf, "SEEN", 4)) {
1279                 cmd_seen(&cmdbuf[5]);
1280         }
1281
1282         else if (!strncasecmp(cmdbuf, "GTSN", 4)) {
1283                 cmd_gtsn(&cmdbuf[5]);
1284         }
1285
1286         else if (!strncasecmp(cmdbuf, "VIEW", 4)) {
1287                 cmd_view(&cmdbuf[5]);
1288         }
1289
1290         else if (!strncasecmp(cmdbuf, "ISME", 4)) {
1291                 cmd_isme(&cmdbuf[5]);
1292         }
1293
1294         else if (!DLoader_Exec_Cmd(cmdbuf)) {
1295                 cprintf("%d Unrecognized or unsupported command.\n",
1296                         ERROR + CMD_NOT_SUPPORTED);
1297                }
1298
1299         unbuffer_output();
1300
1301         /* Run any after-each-command routines registered by modules */
1302         PerformSessionHooks(EVT_CMD);
1303 }
1304
1305
1306 /*
1307  * This loop performs all asynchronous functions.
1308  */
1309 void do_async_loop(void) {
1310         PerformSessionHooks(EVT_ASYNC);
1311 }