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
 256 #ifdef HAVE_LDAP
 257         cprintf("1\n"); /* 1 = yes, this server is LDAP-enabled */
 258 #else
 259         cprintf("0\n"); /* 1 = no, this server is not LDAP-enabled */
 260 #endif
 261
 262 #ifdef ENABLE_AUTOLOGIN
 263         cprintf("1\n"); /* "create new user" never works with autologin */
 264 #else
 265         cprintf("%d\n", config.c_disable_newu); /* otherwise, site defined */
 266 #endif
 267
 268         cprintf("000\n");
 269 }
 270
 271
 272 /*
 273  * returns an asterisk if there are any instant messages waiting,
 274  * space otherwise.
 275  */
 276 char CtdlCheckExpress(void) {
 277         if (CC->FirstExpressMessage == NULL) {
 278                 return(' ');
 279         }
 280         else {
 281                 return('*');
 282         }
 283 }
 284
 285 void cmd_time(void)
 286 {
 287    time_t tv;
 288    struct tm tmp;
 289
 290    tv = time(NULL);
 291    localtime_r(&tv, &tmp);
 292
 293    /* timezone and daylight global variables are not portable. */
 294 #ifdef HAVE_STRUCT_TM_TM_GMTOFF
 295    cprintf("%d %ld|%ld|%d\n", CIT_OK, (long)tv, tmp.tm_gmtoff, tmp.tm_isdst);
 296 #else
 297    cprintf("%d %ld|%ld|%d\n", CIT_OK, (long)tv, timezone, tmp.tm_isdst);
 298 #endif
 299 }
 300
 301
 302 /*
 303  * Check originating host against the public_clients file.  This determines
 304  * whether the client is allowed to change the hostname for this session
 305  * (for example, to show the location of the user rather than the location
 306  * of the client).
 307  */
 308 int is_public_client(void)
 309 {
 310         char buf[1024];
 311         char addrbuf[1024];
 312         FILE *fp;
 313         int i;
 314         struct stat statbuf;
 315         static time_t pc_timestamp = 0;
 316         static char public_clients[SIZ];
 317         static char public_clients_file[SIZ];
 318
 319         snprintf(public_clients_file,
 320                          sizeof public_clients_file,
 321                          "%s/public_clients",
 322                          ctdl_etc_dir);
 323
 324         /*
 325          * Check the time stamp on the public_clients file.  If it's been
 326          * updated since the last time we were here (or if this is the first
 327          * time we've been through the loop), read its contents and learn
 328          * the IP addresses of the listed hosts.
 329          */
 330         if (stat(public_clients_file, &statbuf) != 0) {
 331                 /* No public_clients file exists, so bail out */
 332                 lprintf(CTDL_WARNING, "Warning: '%s' does not exist\n",
 333                                 public_clients_file);
 334                 return(0);
 335         }
 336
 337         if (statbuf.st_mtime > pc_timestamp) {
 338                 begin_critical_section(S_PUBLIC_CLIENTS);
 339                 lprintf(CTDL_INFO, "Loading %s\n", public_clients_file);
 340
 341                 safestrncpy(public_clients, "127.0.0.1", sizeof public_clients);
 342                 if (hostname_to_dotted_quad(addrbuf, config.c_fqdn) == 0) {
 343                         strcat(public_clients, "|");
 344                         strcat(public_clients, addrbuf);
 345                 }
 346
 347                 fp = fopen(public_clients_file, "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(ctdl_message_dir);
 462         dirs[1] = strdup(ctdl_hlp_dir);
 463
 464         snprintf(buf2, sizeof buf2, "%s.%d.%d",
 465                 buf, CC->cs_clientdev, CC->cs_clienttyp);
 466
 467         /* If the client requested "?" then produce a listing */
 468         if (!strcmp(buf, "?")) {
 469                 cprintf("%d %s\n",LISTING_FOLLOWS,buf);
 470                 dp = opendir(dirs[1]);
 471                 if (dp != NULL) {
 472                         while (d = readdir(dp), d != NULL) {
 473                                 if (d->d_name[0] != '.') {
 474                                         cprintf(" %s\n", d->d_name);
 475                                 }
 476                         }
 477                         closedir(dp);
 478                 }
 479                 cprintf("000\n");
 480                 free(dirs[0]);
 481                 free(dirs[1]);
 482                 return;
 483         }
 484
 485         /* Otherwise, look for the requested file by name. */
 486         else {
 487                 mesg_locate(targ, sizeof targ, buf2, 2, (const char **)dirs);
 488                 if (strlen(targ) == 0) {
 489                         snprintf(buf2, sizeof buf2, "%s.%d",
 490                                                         buf, CC->cs_clientdev);
 491                         mesg_locate(targ, sizeof targ, buf2, 2,
 492                                                         (const char **)dirs);
 493                         if (strlen(targ) == 0) {
 494                                 mesg_locate(targ, sizeof targ, buf, 2,
 495                                                         (const char **)dirs);
 496                         }
 497                 }
 498         }
 499
 500         free(dirs[0]);
 501         free(dirs[1]);
 502
 503         if (strlen(targ)==0) {
 504                 cprintf("%d '%s' not found.\n",ERROR + FILE_NOT_FOUND, mname);
 505                 return;
 506         }
 507
 508         mfp = fopen(targ,"r");
 509         if (mfp==NULL) {
 510                 cprintf("%d Cannot open '%s': %s\n",
 511                         ERROR + INTERNAL_ERROR, targ, strerror(errno));
 512                 return;
 513         }
 514         cprintf("%d %s\n",LISTING_FOLLOWS,buf);
 515
 516         while (fgets(buf, (sizeof buf - 1), mfp) != NULL) {
 517                 buf[strlen(buf)-1] = 0;
 518                 do_help_subst(buf);
 519                 cprintf("%s\n",buf);
 520         }
 521
 522         fclose(mfp);
 523         cprintf("000\n");
 524 }
 525
 526
 527 /*
 528  * enter system messages or help
 529  */
 530 void cmd_emsg(char *mname)
 531 {
 532         FILE *mfp;
 533         char targ[256];
 534         char buf[256];
 535         char *dirs[2];
 536         int a;
 537
 538         unbuffer_output();
 539
 540         if (CtdlAccessCheck(ac_aide)) return;
 541
 542         extract_token(buf, mname, 0, '|', sizeof buf);
 543         for (a=0; a<strlen(buf); ++a) {         /* security measure */
 544                 if (buf[a] == '/') buf[a] = '.';
 545         }
 546
 547         dirs[0] = strdup(ctdl_message_dir);
 548         dirs[1] = strdup(ctdl_hlp_dir);
 549
 550         mesg_locate(targ, sizeof targ, buf, 2, (const char**)dirs);
 551         free(dirs[0]);
 552         free(dirs[1]);
 553
 554         if (strlen(targ)==0) {
 555                 snprintf(targ, sizeof targ,
 556                                  "%s/%s",
 557                                  ctdl_hlp_dir, buf);
 558         }
 559
 560         mfp = fopen(targ,"w");
 561         if (mfp==NULL) {
 562                 cprintf("%d Cannot open '%s': %s\n",
 563                         ERROR + INTERNAL_ERROR, targ, strerror(errno));
 564                 return;
 565         }
 566         cprintf("%d %s\n", SEND_LISTING, targ);
 567
 568         while (client_getln(buf, sizeof buf), strcmp(buf, "000")) {
 569                 fprintf(mfp, "%s\n", buf);
 570         }
 571
 572         fclose(mfp);
 573 }
 574
 575
 576 /* Don't show the names of private rooms unless the viewing
 577  * user also knows the rooms.
 578  */
 579 void GenerateRoomDisplay(char *real_room,
 580                         struct CitContext *viewed,
 581                         struct CitContext *viewer) {
 582
 583         int ra;
 584
 585         strcpy(real_room, viewed->room.QRname);
 586         if (viewed->room.QRflags & QR_MAILBOX) {
 587                 strcpy(real_room, &real_room[11]);
 588         }
 589         if (viewed->room.QRflags & QR_PRIVATE) {
 590                 CtdlRoomAccess(&viewed->room, &viewer->user, &ra, NULL);
 591                 if ( (ra & UA_KNOWN) == 0) {
 592                         strcpy(real_room, "<private room>");
 593                 }
 594         }
 595
 596         if (viewed->cs_flags & CS_CHAT) {
 597                 while (strlen(real_room) < 14)
 598                         strcat(real_room, " ");
 599
 600                 strcpy(&real_room[14], "<chat>");
 601         }
 602
 603 }
 604
 605 /*
 606  * Convenience function.
 607  */
 608 int CtdlAccessCheck(int required_level) {
 609
 610         if (CC->internal_pgm) return(0);
 611         if (required_level >= ac_internal) {
 612                 cprintf("%d This is not a user-level command.\n",
 613                         ERROR + HIGHER_ACCESS_REQUIRED);
 614                 return(-1);
 615         }
 616
 617         if ((required_level >= ac_logged_in) && (CC->logged_in == 0)) {
 618                 cprintf("%d Not logged in.\n", ERROR + NOT_LOGGED_IN);
 619                 return(-1);
 620         }
 621
 622         if (CC->user.axlevel >= 6) return(0);
 623         if (required_level >= ac_aide) {
 624                 cprintf("%d This command requires Aide access.\n",
 625                         ERROR + HIGHER_ACCESS_REQUIRED);
 626                 return(-1);
 627         }
 628
 629         if (is_room_aide()) return(0);
 630         if (required_level >= ac_room_aide) {
 631                 cprintf("%d This command requires Aide or Room Aide access.\n",
 632                         ERROR + HIGHER_ACCESS_REQUIRED);
 633                 return(-1);
 634         }
 635
 636         /* shhh ... succeed quietly */
 637         return(0);
 638 }
 639
 640
 641
 642 /*
 643  * Terminate another running session
 644  */
 645 void cmd_term(char *cmdbuf)
 646 {
 647         int session_num;
 648         struct CitContext *ccptr;
 649         int found_it = 0;
 650         int allowed = 0;
 651
 652         session_num = extract_int(cmdbuf, 0);
 653         if (session_num == CC->cs_pid) {
 654                 cprintf("%d You can't kill your own session.\n", ERROR + ILLEGAL_VALUE);
 655                 return;
 656         }
 657
 658         lprintf(CTDL_DEBUG, "Locating session to kill\n");
 659         begin_critical_section(S_SESSION_TABLE);
 660         for (ccptr = ContextList; ccptr != NULL; ccptr = ccptr->next) {
 661                 if (session_num == ccptr->cs_pid) {
 662                         found_it = 1;
 663                         if ((ccptr->user.usernum == CC->user.usernum)
 664                            || (CC->user.axlevel >= 6)) {
 665                                 allowed = 1;
 666                                 ccptr->kill_me = 1;
 667                         }
 668                         else {
 669                                 allowed = 0;
 670                         }
 671                 }
 672         }
 673         end_critical_section(S_SESSION_TABLE);
 674
 675         if (found_it) {
 676                 if (allowed) {
 677                         cprintf("%d Session terminated.\n", CIT_OK);
 678                 }
 679                 else {
 680                         cprintf("%d You are not allowed to do that.\n",
 681                                 ERROR + HIGHER_ACCESS_REQUIRED);
 682                 }
 683         }
 684         else {
 685                 cprintf("%d No such session.\n", ERROR + ILLEGAL_VALUE);
 686         }
 687 }
 688
 689
 690
 691
 692
 693 /*
 694  * get the paginator prompt
 695  */
 696 void cmd_more(void) {
 697         cprintf("%d %s\n", CIT_OK, config.c_moreprompt);
 698 }
 699
 700 /*
 701  * echo
 702  */
 703 void cmd_echo(char *etext)
 704 {
 705         cprintf("%d %s\n", CIT_OK, etext);
 706 }
 707
 708
 709
 710 /*
 711  * identify as internal program
 712  */
 713 void cmd_ipgm(char *argbuf)
 714 {
 715         int secret;
 716
 717         secret = extract_int(argbuf, 0);
 718
 719         /* For security reasons, we do NOT allow this command to run
 720          * over the network.  Local sockets only.
 721          */
 722         if (!CC->is_local_socket) {
 723                 sleep(5);
 724                 cprintf("%d Authentication failed.\n",
 725                         ERROR + PASSWORD_REQUIRED);
 726         }
 727         else if (secret == config.c_ipgm_secret) {
 728                 CC->internal_pgm = 1;
 729                 strcpy(CC->curr_user, "<internal program>");
 730                 CC->cs_flags = CC->cs_flags|CS_STEALTH;
 731                 cprintf("%d Authenticated as an internal program.\n", CIT_OK);
 732         }
 733         else {
 734                 sleep(5);
 735                 cprintf("%d Authentication failed.\n",
 736                         ERROR + PASSWORD_REQUIRED);
 737                 lprintf(CTDL_ERR, "Warning: ipgm authentication failed.\n");
 738                 CC->kill_me = 1;
 739         }
 740
 741         /* Now change the ipgm secret for the next round.
 742          * (Disabled because it breaks concurrent scripts.  The fact that
 743          * we no longer accept IPGM over the network should be sufficient
 744          * to prevent brute-force attacks.  If you don't agree, uncomment
 745          * this block.)
 746         get_config();
 747         config.c_ipgm_secret = rand();
 748         put_config();
 749         */
 750 }
 751
 752
 753 /*
 754  * Shut down the server
 755  */
 756 void cmd_down(void) {
 757
 758         if (CtdlAccessCheck(ac_aide)) return;
 759
 760         cprintf("%d Shutting down server.  Goodbye.\n", CIT_OK);
 761         time_to_die = 1;
 762 }
 763
 764 /*
 765  * Schedule or cancel a server shutdown
 766  */
 767 void cmd_scdn(char *argbuf)
 768 {
 769         int new_state;
 770
 771         if (CtdlAccessCheck(ac_aide)) return;
 772
 773         new_state = extract_int(argbuf, 0);
 774         if ((new_state == 0) || (new_state == 1)) {
 775                 ScheduledShutdown = new_state;
 776         }
 777         cprintf("%d %d\n", CIT_OK, ScheduledShutdown);
 778 }
 779
 780
 781 /*
 782  * Set or unset asynchronous protocol mode
 783  */
 784 void cmd_asyn(char *argbuf)
 785 {
 786         int new_state;
 787
 788         new_state = extract_int(argbuf, 0);
 789         if ((new_state == 0) || (new_state == 1)) {
 790                 CC->is_async = new_state;
 791         }
 792         cprintf("%d %d\n", CIT_OK, CC->is_async);
 793 }
 794
 795
 796 /*
 797  * Generate a "nonce" for APOP-style authentication.
 798  *
 799  * RFC 1725 et al specify a PID to be placed in front of the nonce.
 800  * Quoth BTX: That would be stupid.
 801  */
 802 void generate_nonce(struct CitContext *con) {
 803         struct timeval tv;
 804
 805         memset(con->cs_nonce, NONCE_SIZE, 0);
 806         gettimeofday(&tv, NULL);
 807         memset(con->cs_nonce, NONCE_SIZE, 0);
 808         snprintf(con->cs_nonce, NONCE_SIZE, "<%d%ld@%s>",
 809                 rand(), (long)tv.tv_usec, config.c_fqdn);
 810 }
 811
 812
 813
 814
 815 /*
 816  * Back-end function for starting a session
 817  */
 818 void begin_session(struct CitContext *con)
 819 {
 820         int len;
 821         struct sockaddr_in sin;
 822
 823         /*
 824          * Initialize some variables specific to our context.
 825          */
 826         con->logged_in = 0;
 827         con->internal_pgm = 0;
 828         con->download_fp = NULL;
 829         con->upload_fp = NULL;
 830         con->FirstExpressMessage = NULL;
 831         time(&con->lastcmd);
 832         time(&con->lastidle);
 833         strcpy(con->lastcmdname, "    ");
 834         strcpy(con->cs_clientname, "(unknown)");
 835         strcpy(con->curr_user, NLI);
 836         strcpy(con->net_node, "");
 837         strcpy(con->fake_username, "");
 838         strcpy(con->fake_postname, "");
 839         strcpy(con->fake_hostname, "");
 840         strcpy(con->fake_roomname, "");
 841         generate_nonce(con);
 842         safestrncpy(con->cs_host, config.c_fqdn, sizeof con->cs_host);
 843         safestrncpy(con->cs_addr, "", sizeof con->cs_addr);
 844         con->cs_host[sizeof con->cs_host - 1] = 0;
 845         len = sizeof sin;
 846         if (!CC->is_local_socket) {
 847                 if (!getpeername(con->client_socket,
 848                    (struct sockaddr *) &sin, &len))     /* should be socklen_t but doesn't work on Macintosh */
 849                         locate_host(con->cs_host, sizeof con->cs_host,
 850                                 con->cs_addr, sizeof con->cs_addr,
 851                                 &sin.sin_addr);
 852         }
 853         else {
 854                 strcpy(con->cs_host, "");
 855         }
 856         con->cs_flags = 0;
 857         con->upload_type = UPL_FILE;
 858         con->dl_is_net = 0;
 859
 860         con->nologin = 0;
 861         if ((config.c_maxsessions > 0)&&(num_sessions > config.c_maxsessions))
 862                 con->nologin = 1;
 863
 864         lprintf(CTDL_NOTICE, "Session started.\n");
 865
 866         /* Run any session startup routines registered by loadable modules */
 867         PerformSessionHooks(EVT_START);
 868 }
 869
 870
 871 void citproto_begin_session() {
 872         if (CC->nologin==1) {
 873                 cprintf("%d %s: Too many users are already online "
 874                         "(maximum is %d)\n",
 875                         ERROR + MAX_SESSIONS_EXCEEDED,
 876                         config.c_nodename, config.c_maxsessions);
 877         }
 878         else {
 879                 cprintf("%d %s Citadel server ready.\n",
 880                         CIT_OK, config.c_nodename);
 881         }
 882 }
 883
 884
 885
 886
 887 /*
 888  * This loop recognizes all server commands.
 889  */
 890 void do_command_loop(void) {
 891         char cmdbuf[SIZ];
 892
 893         time(&CC->lastcmd);
 894         memset(cmdbuf, 0, sizeof cmdbuf); /* Clear it, just in case */
 895         if (client_getln(cmdbuf, sizeof cmdbuf) < 1) {
 896                 lprintf(CTDL_ERR, "Client disconnected: ending session.\n");
 897                 CC->kill_me = 1;
 898                 return;
 899         }
 900
 901         /* Log the server command, but don't show passwords... */
 902         if ( (strncasecmp(cmdbuf, "PASS", 4))
 903            && (strncasecmp(cmdbuf, "SETP", 4)) ) {
 904                 lprintf(CTDL_INFO, "%s\n", cmdbuf);
 905         }
 906         else {
 907                 lprintf(CTDL_INFO, "<password command sent>\n");
 908         }
 909
 910         buffer_output();
 911
 912         /*
 913          * Let other clients see the last command we executed, and
 914          * update the idle time, but not NOOP, QNOP, PEXP, GEXP, or RWHO.
 915          */
 916         if ( (strncasecmp(cmdbuf, "NOOP", 4))
 917            && (strncasecmp(cmdbuf, "QNOP", 4))
 918            && (strncasecmp(cmdbuf, "PEXP", 4))
 919            && (strncasecmp(cmdbuf, "GEXP", 4))
 920            && (strncasecmp(cmdbuf, "RWHO", 4)) ) {
 921                 strcpy(CC->lastcmdname, "    ");
 922                 safestrncpy(CC->lastcmdname, cmdbuf, sizeof(CC->lastcmdname));
 923                 time(&CC->lastidle);
 924         }
 925
 926         if ((strncasecmp(cmdbuf, "ENT0", 4))
 927            && (strncasecmp(cmdbuf, "MESG", 4))
 928            && (strncasecmp(cmdbuf, "MSGS", 4)))
 929         {
 930            CC->cs_flags &= ~CS_POSTING;
 931         }
 932
 933         if (!strncasecmp(cmdbuf, "NOOP", 4)) {
 934                 cprintf("%d%cok\n", CIT_OK, CtdlCheckExpress() );
 935         }
 936
 937         else if (!strncasecmp(cmdbuf, "QNOP", 4)) {
 938                 /* do nothing, this command returns no response */
 939         }
 940
 941         else if (!strncasecmp(cmdbuf,"QUIT",4)) {
 942                 cprintf("%d Goodbye.\n", CIT_OK);
 943                 CC->kill_me = 1;
 944         }
 945
 946         else if (!strncasecmp(cmdbuf,"ASYN",4)) {
 947                 cmd_asyn(&cmdbuf[5]);
 948         }
 949
 950         else if (!strncasecmp(cmdbuf,"LOUT",4)) {
 951                 if (CC->logged_in) logout(CC);
 952                 cprintf("%d logged out.\n", CIT_OK);
 953         }
 954
 955         else if (!strncasecmp(cmdbuf,"USER",4)) {
 956                 cmd_user(&cmdbuf[5]);
 957         }
 958
 959         else if (!strncasecmp(cmdbuf,"PASS",4)) {
 960                 cmd_pass(&cmdbuf[5]);
 961         }
 962
 963         else if (!strncasecmp(cmdbuf,"NEWU",4)) {
 964                 cmd_newu(&cmdbuf[5]);
 965         }
 966
 967         else if (!strncasecmp(cmdbuf,"CREU",4)) {
 968                 cmd_creu(&cmdbuf[5]);
 969         }
 970
 971         else if (!strncasecmp(cmdbuf,"SETP",4)) {
 972                 cmd_setp(&cmdbuf[5]);
 973         }
 974
 975         else if (!strncasecmp(cmdbuf,"LRMS",4)) {
 976                 cmd_lrms(&cmdbuf[5]);
 977         }
 978
 979         else if (!strncasecmp(cmdbuf,"LKRA",4)) {
 980                 cmd_lkra(&cmdbuf[5]);
 981         }
 982
 983         else if (!strncasecmp(cmdbuf,"LKRN",4)) {
 984                 cmd_lkrn(&cmdbuf[5]);
 985         }
 986
 987         else if (!strncasecmp(cmdbuf,"LKRO",4)) {
 988                 cmd_lkro(&cmdbuf[5]);
 989         }
 990
 991         else if (!strncasecmp(cmdbuf,"LZRM",4)) {
 992                 cmd_lzrm(&cmdbuf[5]);
 993         }
 994
 995         else if (!strncasecmp(cmdbuf,"LPRM",4)) {
 996                 cmd_lprm(&cmdbuf[5]);
 997         }
 998
 999         else if (!strncasecmp(cmdbuf,"GETU",4)) {
1000                 cmd_getu();
1001         }
1002
1003         else if (!strncasecmp(cmdbuf,"SETU",4)) {
1004                 cmd_setu(&cmdbuf[5]);
1005         }
1006
1007         else if (!strncasecmp(cmdbuf,"GOTO",4)) {
1008                 cmd_goto(&cmdbuf[5]);
1009         }
1010
1011         else if (!strncasecmp(cmdbuf,"MSGS",4)) {
1012                 cmd_msgs(&cmdbuf[5]);
1013         }
1014
1015         else if (!strncasecmp(cmdbuf,"WHOK",4)) {
1016                 cmd_whok();
1017         }
1018
1019         else if (!strncasecmp(cmdbuf,"RDIR",4)) {
1020                 cmd_rdir();
1021         }
1022
1023         else if (!strncasecmp(cmdbuf,"EUID",4)) {
1024                 cmd_euid(&cmdbuf[5]);
1025         }
1026
1027         else if (!strncasecmp(cmdbuf,"MSG0",4)) {
1028                 cmd_msg0(&cmdbuf[5]);
1029         }
1030
1031         else if (!strncasecmp(cmdbuf,"MSG2",4)) {
1032                 cmd_msg2(&cmdbuf[5]);
1033         }
1034
1035         else if (!strncasecmp(cmdbuf,"MSG3",4)) {
1036                 cmd_msg3(&cmdbuf[5]);
1037         }
1038
1039         else if (!strncasecmp(cmdbuf,"MSG4",4)) {
1040                 cmd_msg4(&cmdbuf[5]);
1041         }
1042
1043         else if (!strncasecmp(cmdbuf,"MSGP",4)) {
1044                 cmd_msgp(&cmdbuf[5]);
1045         }
1046
1047         else if (!strncasecmp(cmdbuf,"OPNA",4)) {
1048                 cmd_opna(&cmdbuf[5]);
1049         }
1050
1051         else if (!strncasecmp(cmdbuf,"INFO",4)) {
1052                 cmd_info();
1053         }
1054
1055         else if (!strncasecmp(cmdbuf,"SLRP",4)) {
1056                 cmd_slrp(&cmdbuf[5]);
1057         }
1058
1059         else if (!strncasecmp(cmdbuf,"INVT",4)) {
1060                 cmd_invt_kick(&cmdbuf[5],1);
1061         }
1062
1063         else if (!strncasecmp(cmdbuf,"KICK",4)) {
1064                 cmd_invt_kick(&cmdbuf[5],0);
1065         }
1066
1067         else if (!strncasecmp(cmdbuf,"GETR",4)) {
1068                 cmd_getr();
1069         }
1070
1071         else if (!strncasecmp(cmdbuf,"SETR",4)) {
1072                 cmd_setr(&cmdbuf[5]);
1073         }
1074
1075         else if (!strncasecmp(cmdbuf,"GETA",4)) {
1076                 cmd_geta();
1077         }
1078
1079         else if (!strncasecmp(cmdbuf,"SETA",4)) {
1080                 cmd_seta(&cmdbuf[5]);
1081         }
1082
1083         else if (!strncasecmp(cmdbuf,"ENT0",4)) {
1084                 cmd_ent0(&cmdbuf[5]);
1085         }
1086
1087         else if (!strncasecmp(cmdbuf,"RINF",4)) {
1088                 cmd_rinf();
1089         }
1090
1091         else if (!strncasecmp(cmdbuf,"DELE",4)) {
1092                 cmd_dele(&cmdbuf[5]);
1093         }
1094
1095         else if (!strncasecmp(cmdbuf,"KILL",4)) {
1096                 cmd_kill(&cmdbuf[5]);
1097         }
1098
1099         else if (!strncasecmp(cmdbuf,"CRE8",4)) {
1100                 cmd_cre8(&cmdbuf[5]);
1101         }
1102
1103         else if (!strncasecmp(cmdbuf,"MOVE",4)) {
1104                 cmd_move(&cmdbuf[5]);
1105         }
1106
1107         else if (!strncasecmp(cmdbuf,"FORG",4)) {
1108                 cmd_forg();
1109         }
1110
1111         else if (!strncasecmp(cmdbuf,"MESG",4)) {
1112                 cmd_mesg(&cmdbuf[5]);
1113         }
1114
1115         else if (!strncasecmp(cmdbuf,"EMSG",4)) {
1116                 cmd_emsg(&cmdbuf[5]);
1117         }
1118
1119         else if (!strncasecmp(cmdbuf,"GNUR",4)) {
1120                 cmd_gnur();
1121         }
1122
1123         else if (!strncasecmp(cmdbuf,"VALI",4)) {
1124                 cmd_vali(&cmdbuf[5]);
1125         }
1126
1127         else if (!strncasecmp(cmdbuf,"EINF",4)) {
1128                 cmd_einf(&cmdbuf[5]);
1129         }
1130
1131         else if (!strncasecmp(cmdbuf,"LIST",4)) {
1132                 cmd_list(&cmdbuf[5]);
1133         }
1134
1135         else if (!strncasecmp(cmdbuf,"CHEK",4)) {
1136                 cmd_chek();
1137         }
1138
1139         else if (!strncasecmp(cmdbuf,"DELF",4)) {
1140                 cmd_delf(&cmdbuf[5]);
1141         }
1142
1143         else if (!strncasecmp(cmdbuf,"MOVF",4)) {
1144                 cmd_movf(&cmdbuf[5]);
1145         }
1146
1147         else if (!strncasecmp(cmdbuf,"NETF",4)) {
1148                 cmd_netf(&cmdbuf[5]);
1149         }
1150
1151         else if (!strncasecmp(cmdbuf,"OPEN",4)) {
1152                 cmd_open(&cmdbuf[5]);
1153         }
1154
1155         else if (!strncasecmp(cmdbuf,"CLOS",4)) {
1156                 cmd_clos();
1157         }
1158
1159         else if (!strncasecmp(cmdbuf,"UOPN",4)) {
1160                 cmd_uopn(&cmdbuf[5]);
1161         }
1162
1163         else if (!strncasecmp(cmdbuf,"UCLS",4)) {
1164                 cmd_ucls(&cmdbuf[5]);
1165         }
1166
1167         else if (!strncasecmp(cmdbuf,"READ",4)) {
1168                 cmd_read(&cmdbuf[5]);
1169         }
1170
1171         else if (!strncasecmp(cmdbuf,"WRIT",4)) {
1172                 cmd_writ(&cmdbuf[5]);
1173         }
1174
1175         else if (!strncasecmp(cmdbuf,"QUSR",4)) {
1176                 cmd_qusr(&cmdbuf[5]);
1177         }
1178
1179         else if (!strncasecmp(cmdbuf,"ECHO",4)) {
1180                 cmd_echo(&cmdbuf[5]);
1181         }
1182
1183         else if (!strncasecmp(cmdbuf,"OIMG",4)) {
1184                 cmd_oimg(&cmdbuf[5]);
1185         }
1186
1187         else if (!strncasecmp(cmdbuf,"MORE",4)) {
1188                 cmd_more();
1189         }
1190
1191         else if (!strncasecmp(cmdbuf,"NDOP",4)) {
1192                 cmd_ndop(&cmdbuf[5]);
1193         }
1194
1195         else if (!strncasecmp(cmdbuf,"NUOP",4)) {
1196                 cmd_nuop(&cmdbuf[5]);
1197         }
1198
1199         else if (!strncasecmp(cmdbuf,"LFLR",4)) {
1200                 cmd_lflr();
1201         }
1202
1203         else if (!strncasecmp(cmdbuf,"CFLR",4)) {
1204                 cmd_cflr(&cmdbuf[5]);
1205         }
1206
1207         else if (!strncasecmp(cmdbuf,"KFLR",4)) {
1208                 cmd_kflr(&cmdbuf[5]);
1209         }
1210
1211         else if (!strncasecmp(cmdbuf,"EFLR",4)) {
1212                 cmd_eflr(&cmdbuf[5]);
1213         }
1214
1215         else if (!strncasecmp(cmdbuf,"IDEN",4)) {
1216                 cmd_iden(&cmdbuf[5]);
1217         }
1218
1219         else if (!strncasecmp(cmdbuf,"IPGM",4)) {
1220                 cmd_ipgm(&cmdbuf[5]);
1221         }
1222
1223         else if (!strncasecmp(cmdbuf,"TERM",4)) {
1224                 cmd_term(&cmdbuf[5]);
1225         }
1226
1227         else if (!strncasecmp(cmdbuf,"DOWN",4)) {
1228                 cmd_down();
1229         }
1230
1231         else if (!strncasecmp(cmdbuf,"SCDN",4)) {
1232                 cmd_scdn(&cmdbuf[5]);
1233         }
1234
1235         else if (!strncasecmp(cmdbuf, "UIMG", 4)) {
1236                 cmd_uimg(&cmdbuf[5]);
1237         }
1238
1239         else if (!strncasecmp(cmdbuf, "TIME", 4)) {
1240                 cmd_time();
1241         }
1242
1243         else if (!strncasecmp(cmdbuf, "AGUP", 4)) {
1244                 cmd_agup(&cmdbuf[5]);
1245         }
1246
1247         else if (!strncasecmp(cmdbuf, "ASUP", 4)) {
1248                 cmd_asup(&cmdbuf[5]);
1249         }
1250
1251         else if (!strncasecmp(cmdbuf, "GPEX", 4)) {
1252                 cmd_gpex(&cmdbuf[5]);
1253         }
1254
1255         else if (!strncasecmp(cmdbuf, "SPEX", 4)) {
1256                 cmd_spex(&cmdbuf[5]);
1257         }
1258
1259         else if (!strncasecmp(cmdbuf, "CONF", 4)) {
1260                 cmd_conf(&cmdbuf[5]);
1261         }
1262
1263         else if (!strncasecmp(cmdbuf, "SEEN", 4)) {
1264                 cmd_seen(&cmdbuf[5]);
1265         }
1266
1267         else if (!strncasecmp(cmdbuf, "GTSN", 4)) {
1268                 cmd_gtsn(&cmdbuf[5]);
1269         }
1270
1271         else if (!strncasecmp(cmdbuf, "VIEW", 4)) {
1272                 cmd_view(&cmdbuf[5]);
1273         }
1274
1275         else if (!strncasecmp(cmdbuf, "ISME", 4)) {
1276                 cmd_isme(&cmdbuf[5]);
1277         }
1278
1279         else if (!DLoader_Exec_Cmd(cmdbuf)) {
1280                 cprintf("%d Unrecognized or unsupported command.\n",
1281                         ERROR + CMD_NOT_SUPPORTED);
1282                }
1283
1284         unbuffer_output();
1285
1286         /* Run any after-each-command routines registered by modules */
1287         PerformSessionHooks(EVT_CMD);
1288 }
1289
1290
1291 /*
1292  * This loop performs all asynchronous functions.
1293  */
1294 void do_async_loop(void) {
1295         PerformSessionHooks(EVT_ASYNC);
1296 }