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