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 <dirent.h>
  36 #include <errno.h>
  37 #include <limits.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 #include "euidindex.h"
  62
  63 #ifndef HAVE_SNPRINTF
  64 #include "snprintf.h"
  65 #endif
  66
  67 struct CitContext *ContextList = NULL;
  68 struct CitContext* next_session = NULL;
  69 char *unique_session_numbers;
  70 int ScheduledShutdown = 0;
  71 int do_defrag = 0;
  72 time_t server_startup_time;
  73 char pid_file_name[PATH_MAX];
  74
  75 /*
  76  * Various things that need to be initialized at startup
  77  */
  78 void master_startup(void) {
  79         struct timeval tv;
  80         unsigned int seed;
  81         FILE *urandom;
  82         struct ctdlroom qrbuf;
  83         FILE *pidfile_fp;
  84
  85         lprintf(CTDL_DEBUG, "master_startup() started\n");
  86         time(&server_startup_time);
  87
  88         /* pid file.  If we go FSSTND this should end up in 'localstatedir' */
  89         snprintf(pid_file_name, sizeof pid_file_name, "./citadel.pid");
  90         pidfile_fp = fopen(pid_file_name, "w");
  91         if (pidfile_fp != NULL) {
  92                 fprintf(pidfile_fp, "%d\n", (int)getpid());
  93                 fclose(pidfile_fp);
  94         }
  95
  96         lprintf(CTDL_INFO, "Opening databases\n");
  97         open_databases();
  98
  99         if (do_defrag) {
 100                 defrag_databases();
 101         }
 102
 103         check_ref_counts();
 104
 105         lprintf(CTDL_INFO, "Creating base rooms (if necessary)\n");
 106         create_room(config.c_baseroom,  0, "", 0, 1, 0, VIEW_BBS);
 107         create_room(AIDEROOM,           3, "", 0, 1, 0, VIEW_BBS);
 108         create_room(SYSCONFIGROOM,      3, "", 0, 1, 0, VIEW_BBS);
 109         create_room(config.c_twitroom,  0, "", 0, 1, 0, VIEW_BBS);
 110
 111         /* The "Local System Configuration" room doesn't need to be visible */
 112         if (lgetroom(&qrbuf, SYSCONFIGROOM) == 0) {
 113                 qrbuf.QRflags2 |= QR2_SYSTEM;
 114                 lputroom(&qrbuf);
 115         }
 116
 117         /*
 118          * Create a room in which we can deposit "deleted" messages for
 119          * deferred deletion.  This will silently fail if the room already
 120          * exists, and that's perfectly ok, because we want it to exist.
 121          */
 122         create_room(DELETED_MSGS_ROOM, 3, "", 0, 1, 0, VIEW_MAILBOX);
 123
 124         /*
 125          * Make sure it's set to be a "system room" so it doesn't show up
 126          * in the <K>nown rooms list for Aides.  Also set the message expire
 127          * policy to "by count, 1 message" so everything gets deleted all
 128          * the time (we can't set it to 0 because that's invalid, so we keep
 129          * a single message around).
 130          */
 131         if (lgetroom(&qrbuf, DELETED_MSGS_ROOM) == 0) {
 132                 qrbuf.QRflags2 |= QR2_SYSTEM;
 133                 qrbuf.QRep.expire_mode = EXPIRE_NUMMSGS;
 134                 qrbuf.QRep.expire_value = 1;
 135                 lputroom(&qrbuf);
 136         }
 137
 138         lprintf(CTDL_INFO, "Seeding the pseudo-random number generator...\n");
 139         urandom = fopen("/dev/urandom", "r");
 140         if (urandom != NULL) {
 141                 fread(&seed, sizeof seed, 1, urandom);
 142                 fclose(urandom);
 143         }
 144         else {
 145                 gettimeofday(&tv, NULL);
 146                 seed = tv.tv_usec;
 147         }
 148         srandom(seed);
 149
 150         lprintf(CTDL_INFO, "Initializing ipgm secret\n");
 151         get_config();
 152         config.c_ipgm_secret = rand();
 153         put_config();
 154
 155         lprintf(CTDL_DEBUG, "master_startup() finished\n");
 156 }
 157
 158
 159 /*
 160  * Cleanup routine to be called when the server is shutting down.
 161  */
 162 void master_cleanup(int exitcode) {
 163         struct CleanupFunctionHook *fcn;
 164         static int already_cleaning_up = 0;
 165
 166         if (already_cleaning_up) while(1) sleep(1);
 167         already_cleaning_up = 1;
 168
 169         /* Run any cleanup routines registered by loadable modules */
 170         for (fcn = CleanupHookTable; fcn != NULL; fcn = fcn->next) {
 171                 (*fcn->h_function_pointer)();
 172         }
 173
 174         /* Shut down the indexer thread */
 175         lprintf(CTDL_INFO, "Waiting for the indexer thread to shut down\n");
 176         pthread_join(indexer_thread_tid, NULL);
 177
 178         /* Shut down the checkpoint thread */
 179         lprintf(CTDL_INFO, "Waiting for the checkpoint thread to shut down\n");
 180         pthread_join(checkpoint_thread_tid, NULL);
 181
 182         /* Close databases */
 183         lprintf(CTDL_INFO, "Closing databases\n");
 184         close_databases();
 185
 186         /* Do system-dependent stuff */
 187         sysdep_master_cleanup();
 188
 189 #ifdef DEBUG_MEMORY_LEAKS
 190         dump_heap();
 191 #endif
 192
 193         /* Now go away. */
 194         lprintf(CTDL_NOTICE, "citserver: Exiting with status %d\n", exitcode);
 195         fflush(stdout); fflush(stderr);
 196
 197         unlink(pid_file_name);
 198         exit(exitcode);
 199 }
 200
 201
 202
 203 /*
 204  * Terminate a session.
 205  */
 206 void RemoveContext (struct CitContext *con)
 207 {
 208         if (con==NULL) {
 209                 lprintf(CTDL_ERR,
 210                         "WARNING: RemoveContext() called with NULL!\n");
 211                 return;
 212         }
 213         lprintf(CTDL_DEBUG, "RemoveContext() session %d\n", con->cs_pid);
 214
 215         /* Run any cleanup routines registered by loadable modules.
 216          * Note: We have to "become_session()" because the cleanup functions
 217          *       might make references to "CC" assuming it's the right one.
 218          */
 219         become_session(con);
 220         PerformSessionHooks(EVT_STOP);
 221         become_session(NULL);
 222
 223         /* Now handle all of the administrivia. */
 224         lprintf(CTDL_DEBUG, "Calling logout(%d)\n", con->cs_pid);
 225         logout(con);
 226
 227         lprintf(CTDL_NOTICE, "[%3d] Session ended.\n", con->cs_pid);
 228
 229         /* If the client is still connected, blow 'em away. */
 230         lprintf(CTDL_DEBUG, "Closing socket %d\n", con->client_socket);
 231         close(con->client_socket);
 232
 233         lprintf(CTDL_DEBUG, "Done with RemoveContext()\n");
 234 }
 235
 236
 237
 238
 239
 240 /*
 241  * cmd_info()  -  tell the client about this server
 242  */
 243 void cmd_info(void) {
 244         cprintf("%d Server info:\n", LISTING_FOLLOWS);
 245         cprintf("%d\n", CC->cs_pid);
 246         cprintf("%s\n", config.c_nodename);
 247         cprintf("%s\n", config.c_humannode);
 248         cprintf("%s\n", config.c_fqdn);
 249         cprintf("%s\n", CITADEL);
 250         cprintf("%d\n", REV_LEVEL);
 251         cprintf("%s\n", config.c_site_location);
 252         cprintf("%s\n", config.c_sysadm);
 253         cprintf("%d\n", SERVER_TYPE);
 254         cprintf("%s\n", config.c_moreprompt);
 255         cprintf("1\n"); /* 1 = yes, this system supports floors */
 256         cprintf("1\n"); /* 1 = we support the extended paging options */
 257         cprintf("%s\n", CC->cs_nonce);
 258         cprintf("1\n"); /* 1 = yes, this system supports the QNOP command */
 259 #ifdef HAVE_LDAP
 260         cprintf("1\n"); /* 1 = yes, this server is LDAP-enabled */
 261 #else
 262         cprintf("0\n"); /* 1 = no, this server is not LDAP-enabled */
 263 #endif
 264         cprintf("000\n");
 265 }
 266
 267
 268 /*
 269  * returns an asterisk if there are any instant messages waiting,
 270  * space otherwise.
 271  */
 272 char CtdlCheckExpress(void) {
 273         if (CC->FirstExpressMessage == NULL) {
 274                 return(' ');
 275         }
 276         else {
 277                 return('*');
 278         }
 279 }
 280
 281 void cmd_time(void)
 282 {
 283    time_t tv;
 284    struct tm tmp;
 285
 286    tv = time(NULL);
 287    localtime_r(&tv, &tmp);
 288
 289    /* timezone and daylight global variables are not portable. */
 290 #ifdef HAVE_STRUCT_TM_TM_GMTOFF
 291    cprintf("%d %ld|%ld|%d\n", CIT_OK, (long)tv, tmp.tm_gmtoff, tmp.tm_isdst);
 292 #else
 293    cprintf("%d %ld|%ld|%d\n", CIT_OK, (long)tv, timezone, tmp.tm_isdst);
 294 #endif
 295 }
 296
 297
 298 /*
 299  * Check originating host against the public_clients file.  This determines
 300  * whether the client is allowed to change the hostname for this session
 301  * (for example, to show the location of the user rather than the location
 302  * of the client).
 303  */
 304 int is_public_client(void)
 305 {
 306         char buf[1024];
 307         char addrbuf[1024];
 308         FILE *fp;
 309         int i;
 310         struct stat statbuf;
 311         static time_t pc_timestamp = 0;
 312         static char public_clients[SIZ];
 313
 314 #ifndef HAVE_ETC
 315 #define PUBLIC_CLIENTS "./public_clients"
 316 #else
 317 #define PUBLIC_CLIENTS ETC_DIR"/public_clients"
 318 #endif
 319
 320         /*
 321          * Check the time stamp on the public_clients file.  If it's been
 322          * updated since the last time we were here (or if this is the first
 323          * time we've been through the loop), read its contents and learn
 324          * the IP addresses of the listed hosts.
 325          */
 326         if (stat(PUBLIC_CLIENTS, &statbuf) != 0) {
 327                 /* No public_clients file exists, so bail out */
 328                 lprintf(CTDL_WARNING, "Warning: '%s' does not exist\n", PUBLIC_CLIENTS);
 329                 return(0);
 330         }
 331
 332         if (statbuf.st_mtime > pc_timestamp) {
 333                 begin_critical_section(S_PUBLIC_CLIENTS);
 334                 lprintf(CTDL_INFO, "Loading %s\n", PUBLIC_CLIENTS);
 335
 336                 safestrncpy(public_clients, "127.0.0.1", sizeof public_clients);
 337                 if (hostname_to_dotted_quad(addrbuf, config.c_fqdn) == 0) {
 338                         strcat(public_clients, "|");
 339                         strcat(public_clients, addrbuf);
 340                 }
 341
 342                 fp = fopen(
 343 #ifndef HAVE_ETC
 344                                    "."
 345 #else
 346                                    ETC_DIR
 347 #endif
 348                                    "/public_clients", "r");
 349                 if (fp != NULL) while (fgets(buf, sizeof buf, fp)!=NULL) {
 350                         for (i=0; i<strlen(buf); ++i) {
 351                                 if (buf[i] == '#') buf[i] = 0;
 352                         }
 353                         while (isspace((buf[strlen(buf)-1]))) {
 354                                 buf[strlen(buf)-1] = 0;
 355                         }
 356                         if (hostname_to_dotted_quad(addrbuf, buf) == 0) {
 357                                 if ((strlen(public_clients) +
 358                                    strlen(addrbuf) + 2)
 359                                    < sizeof(public_clients)) {
 360                                         strcat(public_clients, addrbuf);
 361                                 }
 362                         }
 363                 }
 364                 fclose(fp);
 365                 pc_timestamp = time(NULL);
 366                 end_critical_section(S_PUBLIC_CLIENTS);
 367         }
 368
 369         lprintf(CTDL_DEBUG, "Checking whether %s is a local or public client\n",
 370                 CC->cs_addr);
 371         for (i=0; i<num_parms(public_clients); ++i) {
 372                 extract_token(addrbuf, public_clients, i, '|', sizeof addrbuf);
 373                 if (!strcasecmp(CC->cs_addr, addrbuf)) {
 374                         lprintf(CTDL_DEBUG, "... yes it is.\n");
 375                         return(1);
 376                 }
 377         }
 378
 379         /* No hits.  This is not a public client. */
 380         lprintf(CTDL_DEBUG, "... no it isn't.\n");
 381         return(0);
 382 }
 383
 384
 385 /*
 386  * the client is identifying itself to the server
 387  */
 388 void cmd_iden(char *argbuf)
 389 {
 390         int dev_code;
 391         int cli_code;
 392         int rev_level;
 393         char desc[128];
 394         char from_host[128];
 395         struct in_addr addr;
 396         int do_lookup = 0;
 397
 398         if (num_parms(argbuf)<4) {
 399                 cprintf("%d usage error\n", ERROR + ILLEGAL_VALUE);
 400                 return;
 401         }
 402
 403         dev_code = extract_int(argbuf,0);
 404         cli_code = extract_int(argbuf,1);
 405         rev_level = extract_int(argbuf,2);
 406         extract_token(desc, argbuf, 3, '|', sizeof desc);
 407
 408         safestrncpy(from_host, config.c_fqdn, sizeof from_host);
 409         from_host[sizeof from_host - 1] = 0;
 410         if (num_parms(argbuf)>=5) extract_token(from_host, argbuf, 4, '|', sizeof from_host);
 411
 412         CC->cs_clientdev = dev_code;
 413         CC->cs_clienttyp = cli_code;
 414         CC->cs_clientver = rev_level;
 415         safestrncpy(CC->cs_clientname, desc, sizeof CC->cs_clientname);
 416         CC->cs_clientname[31] = 0;
 417
 418         if (strlen(from_host) > 0) {
 419                 if (CC->is_local_socket) do_lookup = 1;
 420                 else if (is_public_client()) do_lookup = 1;
 421         }
 422
 423         if (do_lookup) {
 424                 lprintf(CTDL_DEBUG, "Looking up hostname '%s'\n", from_host);
 425                 if ((addr.s_addr = inet_addr(from_host)) != -1) {
 426                         locate_host(CC->cs_host, sizeof CC->cs_host,
 427                                 NULL, 0,
 428                                 &addr);
 429                 }
 430                 else {
 431                         safestrncpy(CC->cs_host, from_host, sizeof CC->cs_host);
 432                         CC->cs_host[sizeof CC->cs_host - 1] = 0;
 433                 }
 434         }
 435
 436         lprintf(CTDL_NOTICE, "Client %d/%d/%01d.%02d (%s) from %s\n",
 437                 dev_code,
 438                 cli_code,
 439                 (rev_level / 100),
 440                 (rev_level % 100),
 441                 desc,
 442                 CC->cs_host);
 443         cprintf("%d Ok\n",CIT_OK);
 444 }
 445
 446
 447 /*
 448  * display system messages or help
 449  */
 450 void cmd_mesg(char *mname)
 451 {
 452         FILE *mfp;
 453         char targ[256];
 454         char buf[256];
 455         char buf2[256];
 456         char *dirs[2];
 457         DIR *dp;
 458         struct dirent *d;
 459
 460         extract_token(buf, mname, 0, '|', sizeof buf);
 461
 462 #ifdef HAVE_DATA_DIR
 463         dirs[0] = strdup(DATA_DIR "/messages");
 464 #else
 465         dirs[0] = strdup("messages");
 466 #endif
 467
 468 #ifdef HAVE_DATA_DIR
 469         dirs[1] = strdup(DATA_DIR "/help");
 470 #else
 471         dirs[1] = strdup("help");
 472 #endif
 473
 474         snprintf(buf2, sizeof buf2, "%s.%d.%d",
 475                 buf, CC->cs_clientdev, CC->cs_clienttyp);
 476
 477         /* If the client requested "?" then produce a listing */
 478         if (!strcmp(buf, "?")) {
 479                 cprintf("%d %s\n",LISTING_FOLLOWS,buf);
 480                 dp = opendir(dirs[1]);
 481                 if (dp != NULL) {
 482                         while (d = readdir(dp), d != NULL) {
 483                                 if (d->d_name[0] != '.') {
 484                                         cprintf(" %s\n", d->d_name);
 485                                 }
 486                         }
 487                         closedir(dp);
 488                 }
 489                 cprintf("000\n");
 490         }
 491
 492         /* Otherwise, look for the requested file by name. */
 493         else {
 494                 mesg_locate(targ, sizeof targ, buf2, 2, (const char **)dirs);
 495                 if (strlen(targ) == 0) {
 496                         snprintf(buf2, sizeof buf2, "%s.%d",
 497                                                         buf, CC->cs_clientdev);
 498                         mesg_locate(targ, sizeof targ, buf2, 2,
 499                                                         (const char **)dirs);
 500                         if (strlen(targ) == 0) {
 501                                 mesg_locate(targ, sizeof targ, buf, 2,
 502                                                         (const char **)dirs);
 503                         }
 504                 }
 505         }
 506
 507         free(dirs[0]);
 508         free(dirs[1]);
 509
 510         if (strlen(targ)==0) {
 511                 cprintf("%d '%s' not found.\n",ERROR + FILE_NOT_FOUND, mname);
 512                 return;
 513         }
 514
 515         mfp = fopen(targ,"r");
 516         if (mfp==NULL) {
 517                 cprintf("%d Cannot open '%s': %s\n",
 518                         ERROR + INTERNAL_ERROR, targ, strerror(errno));
 519                 return;
 520         }
 521         cprintf("%d %s\n",LISTING_FOLLOWS,buf);
 522
 523         while (fgets(buf, (sizeof buf - 1), mfp) != NULL) {
 524                 buf[strlen(buf)-1] = 0;
 525                 do_help_subst(buf);
 526                 cprintf("%s\n",buf);
 527         }
 528
 529         fclose(mfp);
 530         cprintf("000\n");
 531 }
 532
 533
 534 /*
 535  * enter system messages or help
 536  */
 537 void cmd_emsg(char *mname)
 538 {
 539         FILE *mfp;
 540         char targ[256];
 541         char buf[256];
 542         char *dirs[2];
 543         int a;
 544
 545         unbuffer_output();
 546
 547         if (CtdlAccessCheck(ac_aide)) return;
 548
 549         extract_token(buf, mname, 0, '|', sizeof buf);
 550         for (a=0; a<strlen(buf); ++a) {         /* security measure */
 551                 if (buf[a] == '/') buf[a] = '.';
 552         }
 553
 554 #ifdef HAVE_DATA_DIR
 555         dirs[0] = strdup(DATA_DIR "/messages");
 556 #else
 557         dirs[0] = strdup("messages");
 558 #endif
 559
 560 #ifdef HAVE_DATA_DIR
 561         dirs[1] = strdup(DATA_DIR "/help");
 562 #else
 563         dirs[1] = strdup("help");
 564 #endif
 565
 566         mesg_locate(targ, sizeof targ, buf, 2, (const char**)dirs);
 567         free(dirs[0]);
 568         free(dirs[1]);
 569
 570         if (strlen(targ)==0) {
 571                 snprintf(targ, sizeof targ,
 572 #ifndef HAVE_DATA_DIR
 573                          "."
 574 #else
 575                          DATA_DIR
 576 #endif
 577                                  "/help/%s", buf);
 578         }
 579
 580         mfp = fopen(targ,"w");
 581         if (mfp==NULL) {
 582                 cprintf("%d Cannot open '%s': %s\n",
 583                         ERROR + INTERNAL_ERROR, targ, strerror(errno));
 584                 return;
 585         }
 586         cprintf("%d %s\n", SEND_LISTING, targ);
 587
 588         while (client_getln(buf, sizeof buf), strcmp(buf, "000")) {
 589                 fprintf(mfp, "%s\n", buf);
 590         }
 591
 592         fclose(mfp);
 593 }
 594
 595
 596 /* Don't show the names of private rooms unless the viewing
 597  * user also knows the rooms.
 598  */
 599 void GenerateRoomDisplay(char *real_room,
 600                         struct CitContext *viewed,
 601                         struct CitContext *viewer) {
 602
 603         int ra;
 604
 605         strcpy(real_room, viewed->room.QRname);
 606         if (viewed->room.QRflags & QR_MAILBOX) {
 607                 strcpy(real_room, &real_room[11]);
 608         }
 609         if (viewed->room.QRflags & QR_PRIVATE) {
 610                 CtdlRoomAccess(&viewed->room, &viewer->user, &ra, NULL);
 611                 if ( (ra & UA_KNOWN) == 0) {
 612                         strcpy(real_room, "<private room>");
 613                 }
 614         }
 615
 616         if (viewed->cs_flags & CS_CHAT) {
 617                 while (strlen(real_room) < 14)
 618                         strcat(real_room, " ");
 619
 620                 strcpy(&real_room[14], "<chat>");
 621         }
 622
 623 }
 624
 625 /*
 626  * Convenience function.
 627  */
 628 int CtdlAccessCheck(int required_level) {
 629
 630         if (CC->internal_pgm) return(0);
 631         if (required_level >= ac_internal) {
 632                 cprintf("%d This is not a user-level command.\n",
 633                         ERROR + HIGHER_ACCESS_REQUIRED);
 634                 return(-1);
 635         }
 636
 637         if ((required_level >= ac_logged_in) && (CC->logged_in == 0)) {
 638                 cprintf("%d Not logged in.\n", ERROR + NOT_LOGGED_IN);
 639                 return(-1);
 640         }
 641
 642         if (CC->user.axlevel >= 6) return(0);
 643         if (required_level >= ac_aide) {
 644                 cprintf("%d This command requires Aide access.\n",
 645                         ERROR + HIGHER_ACCESS_REQUIRED);
 646                 return(-1);
 647         }
 648
 649         if (is_room_aide()) return(0);
 650         if (required_level >= ac_room_aide) {
 651                 cprintf("%d This command requires Aide or Room Aide access.\n",
 652                         ERROR + HIGHER_ACCESS_REQUIRED);
 653                 return(-1);
 654         }
 655
 656         /* shhh ... succeed quietly */
 657         return(0);
 658 }
 659
 660
 661
 662 /*
 663  * Terminate another running session
 664  */
 665 void cmd_term(char *cmdbuf)
 666 {
 667         int session_num;
 668         struct CitContext *ccptr;
 669         int found_it = 0;
 670         int allowed = 0;
 671
 672         session_num = extract_int(cmdbuf, 0);
 673         if (session_num == CC->cs_pid) {
 674                 cprintf("%d You can't kill your own session.\n", ERROR + ILLEGAL_VALUE);
 675                 return;
 676         }
 677
 678         lprintf(CTDL_DEBUG, "Locating session to kill\n");
 679         begin_critical_section(S_SESSION_TABLE);
 680         for (ccptr = ContextList; ccptr != NULL; ccptr = ccptr->next) {
 681                 if (session_num == ccptr->cs_pid) {
 682                         found_it = 1;
 683                         if ((ccptr->user.usernum == CC->user.usernum)
 684                            || (CC->user.axlevel >= 6)) {
 685                                 allowed = 1;
 686                                 ccptr->kill_me = 1;
 687                         }
 688                         else {
 689                                 allowed = 0;
 690                         }
 691                 }
 692         }
 693         end_critical_section(S_SESSION_TABLE);
 694
 695         if (found_it) {
 696                 if (allowed) {
 697                         cprintf("%d Session terminated.\n", CIT_OK);
 698                 }
 699                 else {
 700                         cprintf("%d You are not allowed to do that.\n",
 701                                 ERROR + HIGHER_ACCESS_REQUIRED);
 702                 }
 703         }
 704         else {
 705                 cprintf("%d No such session.\n", ERROR + ILLEGAL_VALUE);
 706         }
 707 }
 708
 709
 710
 711
 712
 713 /*
 714  * get the paginator prompt
 715  */
 716 void cmd_more(void) {
 717         cprintf("%d %s\n", CIT_OK, config.c_moreprompt);
 718 }
 719
 720 /*
 721  * echo
 722  */
 723 void cmd_echo(char *etext)
 724 {
 725         cprintf("%d %s\n", CIT_OK, etext);
 726 }
 727
 728
 729
 730 /*
 731  * identify as internal program
 732  */
 733 void cmd_ipgm(char *argbuf)
 734 {
 735         int secret;
 736
 737         secret = extract_int(argbuf, 0);
 738
 739         /* For security reasons, we do NOT allow this command to run
 740          * over the network.  Local sockets only.
 741          */
 742         if (!CC->is_local_socket) {
 743                 sleep(5);
 744                 cprintf("%d Authentication failed.\n",
 745                         ERROR + PASSWORD_REQUIRED);
 746         }
 747         else if (secret == config.c_ipgm_secret) {
 748                 CC->internal_pgm = 1;
 749                 strcpy(CC->curr_user, "<internal program>");
 750                 CC->cs_flags = CC->cs_flags|CS_STEALTH;
 751                 cprintf("%d Authenticated as an internal program.\n", CIT_OK);
 752         }
 753         else {
 754                 sleep(5);
 755                 cprintf("%d Authentication failed.\n",
 756                         ERROR + PASSWORD_REQUIRED);
 757                 lprintf(CTDL_ERR, "Warning: ipgm authentication failed.\n");
 758                 CC->kill_me = 1;
 759         }
 760
 761         /* Now change the ipgm secret for the next round.
 762          * (Disabled because it breaks concurrent scripts.  The fact that
 763          * we no longer accept IPGM over the network should be sufficient
 764          * to prevent brute-force attacks.  If you don't agree, uncomment
 765          * this block.)
 766         get_config();
 767         config.c_ipgm_secret = rand();
 768         put_config();
 769         */
 770 }
 771
 772
 773 /*
 774  * Shut down the server
 775  */
 776 void cmd_down(void) {
 777
 778         if (CtdlAccessCheck(ac_aide)) return;
 779
 780         cprintf("%d Shutting down server.  Goodbye.\n", CIT_OK);
 781         time_to_die = 1;
 782 }
 783
 784 /*
 785  * Schedule or cancel a server shutdown
 786  */
 787 void cmd_scdn(char *argbuf)
 788 {
 789         int new_state;
 790
 791         if (CtdlAccessCheck(ac_aide)) return;
 792
 793         new_state = extract_int(argbuf, 0);
 794         if ((new_state == 0) || (new_state == 1)) {
 795                 ScheduledShutdown = new_state;
 796         }
 797         cprintf("%d %d\n", CIT_OK, ScheduledShutdown);
 798 }
 799
 800
 801 /*
 802  * Set or unset asynchronous protocol mode
 803  */
 804 void cmd_asyn(char *argbuf)
 805 {
 806         int new_state;
 807
 808         new_state = extract_int(argbuf, 0);
 809         if ((new_state == 0) || (new_state == 1)) {
 810                 CC->is_async = new_state;
 811         }
 812         cprintf("%d %d\n", CIT_OK, CC->is_async);
 813 }
 814
 815
 816 /*
 817  * Generate a "nonce" for APOP-style authentication.
 818  *
 819  * RFC 1725 et al specify a PID to be placed in front of the nonce.
 820  * Quoth BTX: That would be stupid.
 821  */
 822 void generate_nonce(struct CitContext *con) {
 823         struct timeval tv;
 824
 825         memset(con->cs_nonce, NONCE_SIZE, 0);
 826         gettimeofday(&tv, NULL);
 827         memset(con->cs_nonce, NONCE_SIZE, 0);
 828         snprintf(con->cs_nonce, NONCE_SIZE, "<%d%ld@%s>",
 829                 rand(), (long)tv.tv_usec, config.c_fqdn);
 830 }
 831
 832
 833
 834
 835 /*
 836  * Back-end function for starting a session
 837  */
 838 void begin_session(struct CitContext *con)
 839 {
 840         int len;
 841         struct sockaddr_in sin;
 842
 843         /*
 844          * Initialize some variables specific to our context.
 845          */
 846         con->logged_in = 0;
 847         con->internal_pgm = 0;
 848         con->download_fp = NULL;
 849         con->upload_fp = NULL;
 850         con->FirstExpressMessage = NULL;
 851         time(&con->lastcmd);
 852         time(&con->lastidle);
 853         strcpy(con->lastcmdname, "    ");
 854         strcpy(con->cs_clientname, "(unknown)");
 855         strcpy(con->curr_user, NLI);
 856         strcpy(con->net_node, "");
 857         strcpy(con->fake_username, "");
 858         strcpy(con->fake_postname, "");
 859         strcpy(con->fake_hostname, "");
 860         strcpy(con->fake_roomname, "");
 861         generate_nonce(con);
 862         safestrncpy(con->cs_host, config.c_fqdn, sizeof con->cs_host);
 863         safestrncpy(con->cs_addr, "", sizeof con->cs_addr);
 864         con->cs_host[sizeof con->cs_host - 1] = 0;
 865         len = sizeof sin;
 866         if (!CC->is_local_socket) {
 867                 if (!getpeername(con->client_socket,
 868                    (struct sockaddr *) &sin, &len))     /* should be socklen_t but doesn't work on Macintosh */
 869                         locate_host(con->cs_host, sizeof con->cs_host,
 870                                 con->cs_addr, sizeof con->cs_addr,
 871                                 &sin.sin_addr);
 872         }
 873         else {
 874                 strcpy(con->cs_host, "");
 875         }
 876         con->cs_flags = 0;
 877         con->upload_type = UPL_FILE;
 878         con->dl_is_net = 0;
 879
 880         con->nologin = 0;
 881         if ((config.c_maxsessions > 0)&&(num_sessions > config.c_maxsessions))
 882                 con->nologin = 1;
 883
 884         lprintf(CTDL_NOTICE, "Session started.\n");
 885
 886         /* Run any session startup routines registered by loadable modules */
 887         PerformSessionHooks(EVT_START);
 888 }
 889
 890
 891 void citproto_begin_session() {
 892         if (CC->nologin==1) {
 893                 cprintf("%d %s: Too many users are already online "
 894                         "(maximum is %d)\n",
 895                         ERROR + MAX_SESSIONS_EXCEEDED,
 896                         config.c_nodename, config.c_maxsessions);
 897         }
 898         else {
 899                 cprintf("%d %s Citadel server ready.\n",
 900                         CIT_OK, config.c_nodename);
 901         }
 902 }
 903
 904
 905
 906
 907 /*
 908  * This loop recognizes all server commands.
 909  */
 910 void do_command_loop(void) {
 911         char cmdbuf[SIZ];
 912
 913         time(&CC->lastcmd);
 914         memset(cmdbuf, 0, sizeof cmdbuf); /* Clear it, just in case */
 915         if (client_getln(cmdbuf, sizeof cmdbuf) < 1) {
 916                 lprintf(CTDL_ERR, "Client socket is broken; ending session\n");
 917                 CC->kill_me = 1;
 918                 return;
 919         }
 920
 921         /* Log the server command, but don't show passwords... */
 922         if ( (strncasecmp(cmdbuf, "PASS", 4))
 923            && (strncasecmp(cmdbuf, "SETP", 4)) ) {
 924                 lprintf(CTDL_INFO, "%s\n", cmdbuf);
 925         }
 926         else {
 927                 lprintf(CTDL_INFO, "<password command sent>\n");
 928         }
 929
 930         buffer_output();
 931
 932         /*
 933          * Let other clients see the last command we executed, and
 934          * update the idle time, but not NOOP, QNOP, PEXP, or GEXP.
 935          */
 936         if ( (strncasecmp(cmdbuf, "NOOP", 4))
 937            && (strncasecmp(cmdbuf, "QNOP", 4))
 938            && (strncasecmp(cmdbuf, "PEXP", 4))
 939            && (strncasecmp(cmdbuf, "GEXP", 4)) ) {
 940                 strcpy(CC->lastcmdname, "    ");
 941                 safestrncpy(CC->lastcmdname, cmdbuf, sizeof(CC->lastcmdname));
 942                 time(&CC->lastidle);
 943         }
 944
 945         if ((strncasecmp(cmdbuf, "ENT0", 4))
 946            && (strncasecmp(cmdbuf, "MESG", 4))
 947            && (strncasecmp(cmdbuf, "MSGS", 4)))
 948         {
 949            CC->cs_flags &= ~CS_POSTING;
 950         }
 951
 952         if (!strncasecmp(cmdbuf, "NOOP", 4)) {
 953                 cprintf("%d%cok\n", CIT_OK, CtdlCheckExpress() );
 954         }
 955
 956         else if (!strncasecmp(cmdbuf, "QNOP", 4)) {
 957                 /* do nothing, this command returns no response */
 958         }
 959
 960         else if (!strncasecmp(cmdbuf,"QUIT",4)) {
 961                 cprintf("%d Goodbye.\n", CIT_OK);
 962                 CC->kill_me = 1;
 963         }
 964
 965         else if (!strncasecmp(cmdbuf,"ASYN",4)) {
 966                 cmd_asyn(&cmdbuf[5]);
 967         }
 968
 969         else if (!strncasecmp(cmdbuf,"LOUT",4)) {
 970                 if (CC->logged_in) logout(CC);
 971                 cprintf("%d logged out.\n", CIT_OK);
 972         }
 973
 974         else if (!strncasecmp(cmdbuf,"USER",4)) {
 975                 cmd_user(&cmdbuf[5]);
 976         }
 977
 978         else if (!strncasecmp(cmdbuf,"PASS",4)) {
 979                 cmd_pass(&cmdbuf[5]);
 980         }
 981
 982         else if (!strncasecmp(cmdbuf,"NEWU",4)) {
 983                 cmd_newu(&cmdbuf[5]);
 984         }
 985
 986         else if (!strncasecmp(cmdbuf,"CREU",4)) {
 987                 cmd_creu(&cmdbuf[5]);
 988         }
 989
 990         else if (!strncasecmp(cmdbuf,"SETP",4)) {
 991                 cmd_setp(&cmdbuf[5]);
 992         }
 993
 994         else if (!strncasecmp(cmdbuf,"LRMS",4)) {
 995                 cmd_lrms(&cmdbuf[5]);
 996         }
 997
 998         else if (!strncasecmp(cmdbuf,"LKRA",4)) {
 999                 cmd_lkra(&cmdbuf[5]);
1000         }
1001
1002         else if (!strncasecmp(cmdbuf,"LKRN",4)) {
1003                 cmd_lkrn(&cmdbuf[5]);
1004         }
1005
1006         else if (!strncasecmp(cmdbuf,"LKRO",4)) {
1007                 cmd_lkro(&cmdbuf[5]);
1008         }
1009
1010         else if (!strncasecmp(cmdbuf,"LZRM",4)) {
1011                 cmd_lzrm(&cmdbuf[5]);
1012         }
1013
1014         else if (!strncasecmp(cmdbuf,"LPRM",4)) {
1015                 cmd_lprm(&cmdbuf[5]);
1016         }
1017
1018         else if (!strncasecmp(cmdbuf,"GETU",4)) {
1019                 cmd_getu();
1020         }
1021
1022         else if (!strncasecmp(cmdbuf,"SETU",4)) {
1023                 cmd_setu(&cmdbuf[5]);
1024         }
1025
1026         else if (!strncasecmp(cmdbuf,"GOTO",4)) {
1027                 cmd_goto(&cmdbuf[5]);
1028         }
1029
1030         else if (!strncasecmp(cmdbuf,"MSGS",4)) {
1031                 cmd_msgs(&cmdbuf[5]);
1032         }
1033
1034         else if (!strncasecmp(cmdbuf,"WHOK",4)) {
1035                 cmd_whok();
1036         }
1037
1038         else if (!strncasecmp(cmdbuf,"RDIR",4)) {
1039                 cmd_rdir();
1040         }
1041
1042         else if (!strncasecmp(cmdbuf,"EUID",4)) {
1043                 cmd_euid(&cmdbuf[5]);
1044         }
1045
1046         else if (!strncasecmp(cmdbuf,"MSG0",4)) {
1047                 cmd_msg0(&cmdbuf[5]);
1048         }
1049
1050         else if (!strncasecmp(cmdbuf,"MSG2",4)) {
1051                 cmd_msg2(&cmdbuf[5]);
1052         }
1053
1054         else if (!strncasecmp(cmdbuf,"MSG3",4)) {
1055                 cmd_msg3(&cmdbuf[5]);
1056         }
1057
1058         else if (!strncasecmp(cmdbuf,"MSG4",4)) {
1059                 cmd_msg4(&cmdbuf[5]);
1060         }
1061
1062         else if (!strncasecmp(cmdbuf,"MSGP",4)) {
1063                 cmd_msgp(&cmdbuf[5]);
1064         }
1065
1066         else if (!strncasecmp(cmdbuf,"OPNA",4)) {
1067                 cmd_opna(&cmdbuf[5]);
1068         }
1069
1070         else if (!strncasecmp(cmdbuf,"INFO",4)) {
1071                 cmd_info();
1072         }
1073
1074         else if (!strncasecmp(cmdbuf,"SLRP",4)) {
1075                 cmd_slrp(&cmdbuf[5]);
1076         }
1077
1078         else if (!strncasecmp(cmdbuf,"INVT",4)) {
1079                 cmd_invt_kick(&cmdbuf[5],1);
1080         }
1081
1082         else if (!strncasecmp(cmdbuf,"KICK",4)) {
1083                 cmd_invt_kick(&cmdbuf[5],0);
1084         }
1085
1086         else if (!strncasecmp(cmdbuf,"GETR",4)) {
1087                 cmd_getr();
1088         }
1089
1090         else if (!strncasecmp(cmdbuf,"SETR",4)) {
1091                 cmd_setr(&cmdbuf[5]);
1092         }
1093
1094         else if (!strncasecmp(cmdbuf,"GETA",4)) {
1095                 cmd_geta();
1096         }
1097
1098         else if (!strncasecmp(cmdbuf,"SETA",4)) {
1099                 cmd_seta(&cmdbuf[5]);
1100         }
1101
1102         else if (!strncasecmp(cmdbuf,"ENT0",4)) {
1103                 cmd_ent0(&cmdbuf[5]);
1104         }
1105
1106         else if (!strncasecmp(cmdbuf,"RINF",4)) {
1107                 cmd_rinf();
1108         }
1109
1110         else if (!strncasecmp(cmdbuf,"DELE",4)) {
1111                 cmd_dele(&cmdbuf[5]);
1112         }
1113
1114         else if (!strncasecmp(cmdbuf,"KILL",4)) {
1115                 cmd_kill(&cmdbuf[5]);
1116         }
1117
1118         else if (!strncasecmp(cmdbuf,"CRE8",4)) {
1119                 cmd_cre8(&cmdbuf[5]);
1120         }
1121
1122         else if (!strncasecmp(cmdbuf,"MOVE",4)) {
1123                 cmd_move(&cmdbuf[5]);
1124         }
1125
1126         else if (!strncasecmp(cmdbuf,"FORG",4)) {
1127                 cmd_forg();
1128         }
1129
1130         else if (!strncasecmp(cmdbuf,"MESG",4)) {
1131                 cmd_mesg(&cmdbuf[5]);
1132         }
1133
1134         else if (!strncasecmp(cmdbuf,"EMSG",4)) {
1135                 cmd_emsg(&cmdbuf[5]);
1136         }
1137
1138         else if (!strncasecmp(cmdbuf,"GNUR",4)) {
1139                 cmd_gnur();
1140         }
1141
1142         else if (!strncasecmp(cmdbuf,"VALI",4)) {
1143                 cmd_vali(&cmdbuf[5]);
1144         }
1145
1146         else if (!strncasecmp(cmdbuf,"EINF",4)) {
1147                 cmd_einf(&cmdbuf[5]);
1148         }
1149
1150         else if (!strncasecmp(cmdbuf,"LIST",4)) {
1151                 cmd_list(&cmdbuf[5]);
1152         }
1153
1154         else if (!strncasecmp(cmdbuf,"CHEK",4)) {
1155                 cmd_chek();
1156         }
1157
1158         else if (!strncasecmp(cmdbuf,"DELF",4)) {
1159                 cmd_delf(&cmdbuf[5]);
1160         }
1161
1162         else if (!strncasecmp(cmdbuf,"MOVF",4)) {
1163                 cmd_movf(&cmdbuf[5]);
1164         }
1165
1166         else if (!strncasecmp(cmdbuf,"NETF",4)) {
1167                 cmd_netf(&cmdbuf[5]);
1168         }
1169
1170         else if (!strncasecmp(cmdbuf,"OPEN",4)) {
1171                 cmd_open(&cmdbuf[5]);
1172         }
1173
1174         else if (!strncasecmp(cmdbuf,"CLOS",4)) {
1175                 cmd_clos();
1176         }
1177
1178         else if (!strncasecmp(cmdbuf,"UOPN",4)) {
1179                 cmd_uopn(&cmdbuf[5]);
1180         }
1181
1182         else if (!strncasecmp(cmdbuf,"UCLS",4)) {
1183                 cmd_ucls(&cmdbuf[5]);
1184         }
1185
1186         else if (!strncasecmp(cmdbuf,"READ",4)) {
1187                 cmd_read(&cmdbuf[5]);
1188         }
1189
1190         else if (!strncasecmp(cmdbuf,"WRIT",4)) {
1191                 cmd_writ(&cmdbuf[5]);
1192         }
1193
1194         else if (!strncasecmp(cmdbuf,"QUSR",4)) {
1195                 cmd_qusr(&cmdbuf[5]);
1196         }
1197
1198         else if (!strncasecmp(cmdbuf,"ECHO",4)) {
1199                 cmd_echo(&cmdbuf[5]);
1200         }
1201
1202         else if (!strncasecmp(cmdbuf,"OIMG",4)) {
1203                 cmd_oimg(&cmdbuf[5]);
1204         }
1205
1206         else if (!strncasecmp(cmdbuf,"MORE",4)) {
1207                 cmd_more();
1208         }
1209
1210         else if (!strncasecmp(cmdbuf,"NDOP",4)) {
1211                 cmd_ndop(&cmdbuf[5]);
1212         }
1213
1214         else if (!strncasecmp(cmdbuf,"NUOP",4)) {
1215                 cmd_nuop(&cmdbuf[5]);
1216         }
1217
1218         else if (!strncasecmp(cmdbuf,"LFLR",4)) {
1219                 cmd_lflr();
1220         }
1221
1222         else if (!strncasecmp(cmdbuf,"CFLR",4)) {
1223                 cmd_cflr(&cmdbuf[5]);
1224         }
1225
1226         else if (!strncasecmp(cmdbuf,"KFLR",4)) {
1227                 cmd_kflr(&cmdbuf[5]);
1228         }
1229
1230         else if (!strncasecmp(cmdbuf,"EFLR",4)) {
1231                 cmd_eflr(&cmdbuf[5]);
1232         }
1233
1234         else if (!strncasecmp(cmdbuf,"IDEN",4)) {
1235                 cmd_iden(&cmdbuf[5]);
1236         }
1237
1238         else if (!strncasecmp(cmdbuf,"IPGM",4)) {
1239                 cmd_ipgm(&cmdbuf[5]);
1240         }
1241
1242         else if (!strncasecmp(cmdbuf,"TERM",4)) {
1243                 cmd_term(&cmdbuf[5]);
1244         }
1245
1246         else if (!strncasecmp(cmdbuf,"DOWN",4)) {
1247                 cmd_down();
1248         }
1249
1250         else if (!strncasecmp(cmdbuf,"SCDN",4)) {
1251                 cmd_scdn(&cmdbuf[5]);
1252         }
1253
1254         else if (!strncasecmp(cmdbuf, "UIMG", 4)) {
1255                 cmd_uimg(&cmdbuf[5]);
1256         }
1257
1258         else if (!strncasecmp(cmdbuf, "TIME", 4)) {
1259                 cmd_time();
1260         }
1261
1262         else if (!strncasecmp(cmdbuf, "AGUP", 4)) {
1263                 cmd_agup(&cmdbuf[5]);
1264         }
1265
1266         else if (!strncasecmp(cmdbuf, "ASUP", 4)) {
1267                 cmd_asup(&cmdbuf[5]);
1268         }
1269
1270         else if (!strncasecmp(cmdbuf, "GPEX", 4)) {
1271                 cmd_gpex(&cmdbuf[5]);
1272         }
1273
1274         else if (!strncasecmp(cmdbuf, "SPEX", 4)) {
1275                 cmd_spex(&cmdbuf[5]);
1276         }
1277
1278         else if (!strncasecmp(cmdbuf, "CONF", 4)) {
1279                 cmd_conf(&cmdbuf[5]);
1280         }
1281
1282         else if (!strncasecmp(cmdbuf, "SEEN", 4)) {
1283                 cmd_seen(&cmdbuf[5]);
1284         }
1285
1286         else if (!strncasecmp(cmdbuf, "GTSN", 4)) {
1287                 cmd_gtsn(&cmdbuf[5]);
1288         }
1289
1290         else if (!strncasecmp(cmdbuf, "VIEW", 4)) {
1291                 cmd_view(&cmdbuf[5]);
1292         }
1293
1294         else if (!strncasecmp(cmdbuf, "ISME", 4)) {
1295                 cmd_isme(&cmdbuf[5]);
1296         }
1297
1298         else if (!strncasecmp(cmdbuf, "FUCK", 4)) {
1299                 cprintf("100\n");
1300
1301                 struct CtdlMessage *msg;
1302                 msg = CtdlFetchMessage(3115, 1);
1303                 cprintf("\nCtdlOutputPreLoadedMsg(msg, MT_RFC822, HEADERS_ONLY, 0, 1);\n--\n");
1304                 CtdlOutputPreLoadedMsg(msg, MT_RFC822, HEADERS_ONLY, 0, 1);
1305                 cprintf("--\nCtdlOutputPreLoadedMsg(msg, MT_RFC822, HEADERS_NONE, 0, 1);\n--\n");
1306                 CtdlOutputPreLoadedMsg(msg, MT_RFC822, HEADERS_NONE, 0, 1);
1307                 cprintf("--\nCtdlOutputPreLoadedMsg(msg, MT_RFC822, HEADERS_ALL, 0, 1);\n--\n");
1308                 CtdlOutputPreLoadedMsg(msg, MT_RFC822, HEADERS_ALL, 0, 1);
1309                 cprintf("--\n");
1310                 cprintf("000\n");
1311                 CtdlFreeMessage(msg);
1312         }
1313
1314         else if (!DLoader_Exec_Cmd(cmdbuf)) {
1315                 cprintf("%d Unrecognized or unsupported command.\n",
1316                         ERROR + CMD_NOT_SUPPORTED);
1317                }
1318
1319         unbuffer_output();
1320
1321         /* Run any after-each-command routines registered by modules */
1322         PerformSessionHooks(EVT_CMD);
1323 }
1324
1325
1326 /*
1327  * This loop performs all asynchronous functions.
1328  */
1329 void do_async_loop(void) {
1330         PerformSessionHooks(EVT_ASYNC);
1331 }