citadel/citserver.c

   1 /*
   2  * $Id$
   3  *
   4  * Main source module for the Citadel server
   5  *
   6  */
   7
   8 #include "sysdep.h"
   9 #include <stdlib.h>
  10 #include <unistd.h>
  11 #include <stdio.h>
  12 #include <fcntl.h>
  13 #include <signal.h>
  14 #include <sys/types.h>
  15 #include <sys/stat.h>
  16
  17
  18 #if TIME_WITH_SYS_TIME
  19 # include <sys/time.h>
  20 # include <time.h>
  21 #else
  22 # if HAVE_SYS_TIME_H
  23 #  include <sys/time.h>
  24 # else
  25 #  include <time.h>
  26 # endif
  27 #endif
  28
  29 #include <ctype.h>
  30 #include <string.h>
  31 #include <dirent.h>
  32 #include <errno.h>
  33 #include <limits.h>
  34 #include <netdb.h>
  35 #include <sys/types.h>
  36 #include <sys/socket.h>
  37 #include <netinet/in.h>
  38 #include <arpa/inet.h>
  39 #include "citadel.h"
  40 #include "server.h"
  41 #include "serv_extensions.h"
  42 #include "sysdep_decls.h"
  43 #include "citserver.h"
  44 #include "config.h"
  45 #include "database.h"
  46 #include "housekeeping.h"
  47 #include "user_ops.h"
  48 #include "msgbase.h"
  49 #include "support.h"
  50 #include "locate_host.h"
  51 #include "room_ops.h"
  52 #include "file_ops.h"
  53 #include "policy.h"
  54 #include "control.h"
  55 #include "tools.h"
  56 #include "euidindex.h"
  57
  58 #ifndef HAVE_SNPRINTF
  59 #include "snprintf.h"
  60 #endif
  61
  62 struct CitContext *ContextList = NULL;
  63 struct CitContext* next_session = NULL;
  64 char *unique_session_numbers;
  65 int ScheduledShutdown = 0;
  66 int do_defrag = 0;
  67 time_t server_startup_time;
  68 char pid_file_name[PATH_MAX];
  69
  70 /*
  71  * Various things that need to be initialized at startup
  72  */
  73 void master_startup(void) {
  74         struct timeval tv;
  75         unsigned int seed;
  76         FILE *urandom;
  77         struct ctdlroom qrbuf;
  78         FILE *pidfile_fp;
  79
  80         lprintf(CTDL_DEBUG, "master_startup() started\n");
  81         time(&server_startup_time);
  82
  83         /* pid file.  If we go FSSTND this should end up in 'localstatedir' */
  84         snprintf(pid_file_name, sizeof pid_file_name, "./citadel.pid");
  85         pidfile_fp = fopen(pid_file_name, "w");
  86         if (pidfile_fp != NULL) {
  87                 fprintf(pidfile_fp, "%d\n", (int)getpid());
  88                 fclose(pidfile_fp);
  89         }
  90
  91         lprintf(CTDL_INFO, "Opening databases\n");
  92         open_databases();
  93
  94         if (do_defrag) {
  95                 defrag_databases();
  96         }
  97
  98         check_ref_counts();
  99
 100         lprintf(CTDL_INFO, "Creating base rooms (if necessary)\n");
 101         create_room(config.c_baseroom,  0, "", 0, 1, 0, VIEW_BBS);
 102         create_room(AIDEROOM,           3, "", 0, 1, 0, VIEW_BBS);
 103         create_room(SYSCONFIGROOM,      3, "", 0, 1, 0, VIEW_BBS);
 104         create_room(config.c_twitroom,  0, "", 0, 1, 0, VIEW_BBS);
 105
 106         /* The "Local System Configuration" room doesn't need to be visible */
 107         if (lgetroom(&qrbuf, SYSCONFIGROOM) == 0) {
 108                 qrbuf.QRflags2 |= QR2_SYSTEM;
 109                 lputroom(&qrbuf);
 110         }
 111
 112         /*
 113          * Create a room in which we can deposit "deleted" messages for
 114          * deferred deletion.  This will silently fail if the room already
 115          * exists, and that's perfectly ok, because we want it to exist.
 116          */
 117         create_room(DELETED_MSGS_ROOM, 3, "", 0, 1, 0, VIEW_MAILBOX);
 118
 119         /*
 120          * Make sure it's set to be a "system room" so it doesn't show up
 121          * in the <K>nown rooms list for Aides.  Also set the message expire
 122          * policy to "by count, 1 message" so everything gets deleted all
 123          * the time (we can't set it to 0 because that's invalid, so we keep
 124          * a single message around).
 125          */
 126         if (lgetroom(&qrbuf, DELETED_MSGS_ROOM) == 0) {
 127                 qrbuf.QRflags2 |= QR2_SYSTEM;
 128                 qrbuf.QRep.expire_mode = EXPIRE_NUMMSGS;
 129                 qrbuf.QRep.expire_value = 1;
 130                 lputroom(&qrbuf);
 131         }
 132
 133         lprintf(CTDL_INFO, "Seeding the pseudo-random number generator...\n");
 134         urandom = fopen("/dev/urandom", "r");
 135         if (urandom != NULL) {
 136                 fread(&seed, sizeof seed, 1, urandom);
 137                 fclose(urandom);
 138         }
 139         else {
 140                 gettimeofday(&tv, NULL);
 141                 seed = tv.tv_usec;
 142         }
 143         srandom(seed);
 144
 145         lprintf(CTDL_INFO, "Initializing ipgm secret\n");
 146         get_config();
 147         config.c_ipgm_secret = rand();
 148         put_config();
 149
 150         lprintf(CTDL_DEBUG, "master_startup() finished\n");
 151 }
 152
 153
 154 /*
 155  * Cleanup routine to be called when the server is shutting down.
 156  */
 157 void master_cleanup(int exitcode) {
 158         struct CleanupFunctionHook *fcn;
 159         static int already_cleaning_up = 0;
 160
 161         if (already_cleaning_up) while(1) sleep(1);
 162         already_cleaning_up = 1;
 163
 164         /* Run any cleanup routines registered by loadable modules */
 165         for (fcn = CleanupHookTable; fcn != NULL; fcn = fcn->next) {
 166                 (*fcn->h_function_pointer)();
 167         }
 168
 169         /* Shut down the indexer thread */
 170         lprintf(CTDL_INFO, "Waiting for the indexer thread to shut down\n");
 171         pthread_join(indexer_thread_tid, NULL);
 172
 173         /* Shut down the checkpoint thread */
 174         lprintf(CTDL_INFO, "Waiting for the checkpoint thread to shut down\n");
 175         pthread_join(checkpoint_thread_tid, NULL);
 176
 177         /* Close databases */
 178         lprintf(CTDL_INFO, "Closing databases\n");
 179         close_databases();
 180
 181         /* Do system-dependent stuff */
 182         sysdep_master_cleanup();
 183
 184 #ifdef DEBUG_MEMORY_LEAKS
 185         dump_heap();
 186 #endif
 187
 188         /* If the operator requested a halt but not an exit, halt here. */
 189         if (shutdown_and_halt) {
 190                 lprintf(CTDL_NOTICE, "citserver: Halting server without exiting.\n");
 191                 fflush(stdout); fflush(stderr);
 192                 while(1) {
 193                         sleep(32767);
 194                 }
 195         }
 196
 197         /* Now go away. */
 198         lprintf(CTDL_NOTICE, "citserver: Exiting with status %d\n", exitcode);
 199         fflush(stdout); fflush(stderr);
 200
 201         unlink(pid_file_name);
 202         exit(exitcode);
 203 }
 204
 205
 206
 207 /*
 208  * Terminate a session.
 209  */
 210 void RemoveContext (struct CitContext *con)
 211 {
 212         if (con==NULL) {
 213                 lprintf(CTDL_ERR,
 214                         "WARNING: RemoveContext() called with NULL!\n");
 215                 return;
 216         }
 217         lprintf(CTDL_DEBUG, "RemoveContext() session %d\n", con->cs_pid);
 218
 219         /* Run any cleanup routines registered by loadable modules.
 220          * Note: We have to "become_session()" because the cleanup functions
 221          *       might make references to "CC" assuming it's the right one.
 222          */
 223         become_session(con);
 224         PerformSessionHooks(EVT_STOP);
 225         become_session(NULL);
 226
 227         /* Now handle all of the administrivia. */
 228         lprintf(CTDL_DEBUG, "Calling logout(%d)\n", con->cs_pid);
 229         logout(con);
 230
 231         lprintf(CTDL_NOTICE, "[%3d] Session ended.\n", con->cs_pid);
 232
 233         /* If the client is still connected, blow 'em away. */
 234         lprintf(CTDL_DEBUG, "Closing socket %d\n", con->client_socket);
 235         close(con->client_socket);
 236
 237         lprintf(CTDL_DEBUG, "Done with RemoveContext()\n");
 238 }
 239
 240
 241
 242
 243
 244 /*
 245  * cmd_info()  -  tell the client about this server
 246  */
 247 void cmd_info(void) {
 248         cprintf("%d Server info:\n", LISTING_FOLLOWS);
 249         cprintf("%d\n", CC->cs_pid);
 250         cprintf("%s\n", config.c_nodename);
 251         cprintf("%s\n", config.c_humannode);
 252         cprintf("%s\n", config.c_fqdn);
 253         cprintf("%s\n", CITADEL);
 254         cprintf("%d\n", REV_LEVEL);
 255         cprintf("%s\n", config.c_site_location);
 256         cprintf("%s\n", config.c_sysadm);
 257         cprintf("%d\n", SERVER_TYPE);
 258         cprintf("%s\n", config.c_moreprompt);
 259         cprintf("1\n"); /* 1 = yes, this system supports floors */
 260         cprintf("1\n"); /* 1 = we support the extended paging options */
 261         cprintf("%s\n", CC->cs_nonce);
 262         cprintf("1\n"); /* 1 = yes, this system supports the QNOP command */
 263
 264 #ifdef HAVE_LDAP
 265         cprintf("1\n"); /* 1 = yes, this server is LDAP-enabled */
 266 #else
 267         cprintf("0\n"); /* 1 = no, this server is not LDAP-enabled */
 268 #endif
 269
 270 #ifdef ENABLE_AUTOLOGIN
 271         cprintf("1\n"); /* "create new user" never works with autologin */
 272 #else
 273         cprintf("%d\n", config.c_disable_newu); /* otherwise, site defined */
 274 #endif
 275
 276         cprintf("%s\n", config.c_default_cal_zone);
 277
 278         cprintf("000\n");
 279 }
 280
 281
 282 /*
 283  * returns an asterisk if there are any instant messages waiting,
 284  * space otherwise.
 285  */
 286 char CtdlCheckExpress(void) {
 287         if (CC->FirstExpressMessage == NULL) {
 288                 return(' ');
 289         }
 290         else {
 291                 return('*');
 292         }
 293 }
 294
 295 void cmd_time(void)
 296 {
 297    time_t tv;
 298    struct tm tmp;
 299
 300    tv = time(NULL);
 301    localtime_r(&tv, &tmp);
 302
 303    /* timezone and daylight global variables are not portable. */
 304 #ifdef HAVE_STRUCT_TM_TM_GMTOFF
 305    cprintf("%d %ld|%ld|%d\n", CIT_OK, (long)tv, tmp.tm_gmtoff, tmp.tm_isdst);
 306 #else
 307    cprintf("%d %ld|%ld|%d\n", CIT_OK, (long)tv, timezone, tmp.tm_isdst);
 308 #endif
 309 }
 310
 311
 312 /*
 313  * Check originating host against the public_clients file.  This determines
 314  * whether the client is allowed to change the hostname for this session
 315  * (for example, to show the location of the user rather than the location
 316  * of the client).
 317  */
 318 int is_public_client(void)
 319 {
 320         char buf[1024];
 321         char addrbuf[1024];
 322         FILE *fp;
 323         int i;
 324         struct stat statbuf;
 325         static time_t pc_timestamp = 0;
 326         static char public_clients[SIZ];
 327         static char public_clients_file[SIZ];
 328
 329         snprintf(public_clients_file,
 330                          sizeof public_clients_file,
 331                          "%s/public_clients",
 332                          ctdl_etc_dir);
 333
 334         /*
 335          * Check the time stamp on the public_clients file.  If it's been
 336          * updated since the last time we were here (or if this is the first
 337          * time we've been through the loop), read its contents and learn
 338          * the IP addresses of the listed hosts.
 339          */
 340         if (stat(public_clients_file, &statbuf) != 0) {
 341                 /* No public_clients file exists, so bail out */
 342                 lprintf(CTDL_WARNING, "Warning: '%s' does not exist\n",
 343                                 public_clients_file);
 344                 return(0);
 345         }
 346
 347         if (statbuf.st_mtime > pc_timestamp) {
 348                 begin_critical_section(S_PUBLIC_CLIENTS);
 349                 lprintf(CTDL_INFO, "Loading %s\n", public_clients_file);
 350
 351                 safestrncpy(public_clients, "127.0.0.1", sizeof public_clients);
 352                 if (hostname_to_dotted_quad(addrbuf, config.c_fqdn) == 0) {
 353                         strcat(public_clients, "|");
 354                         strcat(public_clients, addrbuf);
 355                 }
 356
 357                 fp = fopen(public_clients_file, "r");
 358                 if (fp != NULL) while (fgets(buf, sizeof buf, fp)!=NULL) {
 359                         for (i=0; i<strlen(buf); ++i) {
 360                                 if (buf[i] == '#') buf[i] = 0;
 361                         }
 362                         while (isspace((buf[strlen(buf)-1]))) {
 363                                 buf[strlen(buf)-1] = 0;
 364                         }
 365                         if (hostname_to_dotted_quad(addrbuf, buf) == 0) {
 366                                 if ((strlen(public_clients) +
 367                                    strlen(addrbuf) + 2)
 368                                    < sizeof(public_clients)) {
 369                                         strcat(public_clients, "|");
 370                                         strcat(public_clients, addrbuf);
 371                                 }
 372                         }
 373                 }
 374                 fclose(fp);
 375                 pc_timestamp = time(NULL);
 376                 end_critical_section(S_PUBLIC_CLIENTS);
 377         }
 378
 379         lprintf(CTDL_DEBUG, "Checking whether %s is a local or public client\n",
 380                 CC->cs_addr);
 381         for (i=0; i<num_parms(public_clients); ++i) {
 382                 extract_token(addrbuf, public_clients, i, '|', sizeof addrbuf);
 383                 if (!strcasecmp(CC->cs_addr, addrbuf)) {
 384                         lprintf(CTDL_DEBUG, "... yes it is.\n");
 385                         return(1);
 386                 }
 387         }
 388
 389         /* No hits.  This is not a public client. */
 390         lprintf(CTDL_DEBUG, "... no it isn't.\n");
 391         return(0);
 392 }
 393
 394
 395 /*
 396  * the client is identifying itself to the server
 397  */
 398 void cmd_iden(char *argbuf)
 399 {
 400         int dev_code;
 401         int cli_code;
 402         int rev_level;
 403         char desc[128];
 404         char from_host[128];
 405         struct in_addr addr;
 406         int do_lookup = 0;
 407
 408         if (num_parms(argbuf)<4) {
 409                 cprintf("%d usage error\n", ERROR + ILLEGAL_VALUE);
 410                 return;
 411         }
 412
 413         dev_code = extract_int(argbuf,0);
 414         cli_code = extract_int(argbuf,1);
 415         rev_level = extract_int(argbuf,2);
 416         extract_token(desc, argbuf, 3, '|', sizeof desc);
 417
 418         safestrncpy(from_host, config.c_fqdn, sizeof from_host);
 419         from_host[sizeof from_host - 1] = 0;
 420         if (num_parms(argbuf)>=5) extract_token(from_host, argbuf, 4, '|', sizeof from_host);
 421
 422         CC->cs_clientdev = dev_code;
 423         CC->cs_clienttyp = cli_code;
 424         CC->cs_clientver = rev_level;
 425         safestrncpy(CC->cs_clientname, desc, sizeof CC->cs_clientname);
 426         CC->cs_clientname[31] = 0;
 427
 428         if (strlen(from_host) > 0) {
 429                 if (CC->is_local_socket) do_lookup = 1;
 430                 else if (is_public_client()) do_lookup = 1;
 431         }
 432
 433         if (do_lookup) {
 434                 lprintf(CTDL_DEBUG, "Looking up hostname '%s'\n", from_host);
 435                 if ((addr.s_addr = inet_addr(from_host)) != -1) {
 436                         locate_host(CC->cs_host, sizeof CC->cs_host,
 437                                 NULL, 0,
 438                                 &addr);
 439                 }
 440                 else {
 441                         safestrncpy(CC->cs_host, from_host, sizeof CC->cs_host);
 442                         CC->cs_host[sizeof CC->cs_host - 1] = 0;
 443                 }
 444         }
 445
 446         lprintf(CTDL_NOTICE, "Client %d/%d/%01d.%02d (%s) from %s\n",
 447                 dev_code,
 448                 cli_code,
 449                 (rev_level / 100),
 450                 (rev_level % 100),
 451                 desc,
 452                 CC->cs_host);
 453         cprintf("%d Ok\n",CIT_OK);
 454 }
 455
 456
 457 /*
 458  * display system messages or help
 459  */
 460 void cmd_mesg(char *mname)
 461 {
 462         FILE *mfp;
 463         char targ[256];
 464         char buf[256];
 465         char buf2[256];
 466         char *dirs[2];
 467         DIR *dp;
 468         struct dirent *d;
 469
 470         extract_token(buf, mname, 0, '|', sizeof buf);
 471
 472         dirs[0] = strdup(ctdl_message_dir);
 473         dirs[1] = strdup(ctdl_hlp_dir);
 474
 475         snprintf(buf2, sizeof buf2, "%s.%d.%d",
 476                 buf, CC->cs_clientdev, CC->cs_clienttyp);
 477
 478         /* If the client requested "?" then produce a listing */
 479         if (!strcmp(buf, "?")) {
 480                 cprintf("%d %s\n", LISTING_FOLLOWS, buf);
 481                 dp = opendir(dirs[1]);
 482                 if (dp != NULL) {
 483                         while (d = readdir(dp), d != NULL) {
 484                                 if (d->d_name[0] != '.') {
 485                                         cprintf(" %s\n", d->d_name);
 486                                 }
 487                         }
 488                         closedir(dp);
 489                 }
 490                 cprintf("000\n");
 491                 free(dirs[0]);
 492                 free(dirs[1]);
 493                 return;
 494         }
 495
 496         /* Otherwise, look for the requested file by name. */
 497         else {
 498                 mesg_locate(targ, sizeof targ, buf2, 2, (const char **)dirs);
 499                 if (strlen(targ) == 0) {
 500                         snprintf(buf2, sizeof buf2, "%s.%d",
 501                                                         buf, CC->cs_clientdev);
 502                         mesg_locate(targ, sizeof targ, buf2, 2,
 503                                                         (const char **)dirs);
 504                         if (strlen(targ) == 0) {
 505                                 mesg_locate(targ, sizeof targ, buf, 2,
 506                                                         (const char **)dirs);
 507                         }
 508                 }
 509         }
 510
 511         free(dirs[0]);
 512         free(dirs[1]);
 513
 514         if (strlen(targ)==0) {
 515                 cprintf("%d '%s' not found.  (Searching in %s and %s)\n",
 516                         ERROR + FILE_NOT_FOUND,
 517                         mname,
 518                         ctdl_message_dir,
 519                         ctdl_hlp_dir
 520                 );
 521                 return;
 522         }
 523
 524         mfp = fopen(targ, "r");
 525         if (mfp==NULL) {
 526                 cprintf("%d Cannot open '%s': %s\n",
 527                         ERROR + INTERNAL_ERROR, targ, strerror(errno));
 528                 return;
 529         }
 530         cprintf("%d %s\n", LISTING_FOLLOWS,buf);
 531
 532         while (fgets(buf, (sizeof buf - 1), mfp) != NULL) {
 533                 buf[strlen(buf)-1] = 0;
 534                 do_help_subst(buf);
 535                 cprintf("%s\n",buf);
 536         }
 537
 538         fclose(mfp);
 539         cprintf("000\n");
 540 }
 541
 542
 543 /*
 544  * enter system messages or help
 545  */
 546 void cmd_emsg(char *mname)
 547 {
 548         FILE *mfp;
 549         char targ[256];
 550         char buf[256];
 551         char *dirs[2];
 552         int a;
 553
 554         unbuffer_output();
 555
 556         if (CtdlAccessCheck(ac_aide)) return;
 557
 558         extract_token(buf, mname, 0, '|', sizeof buf);
 559         for (a=0; a<strlen(buf); ++a) {         /* security measure */
 560                 if (buf[a] == '/') buf[a] = '.';
 561         }
 562
 563         dirs[0] = strdup(ctdl_message_dir);
 564         dirs[1] = strdup(ctdl_hlp_dir);
 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                                  "%s/%s",
 573                                  ctdl_hlp_dir, buf);
 574         }
 575
 576         mfp = fopen(targ,"w");
 577         if (mfp==NULL) {
 578                 cprintf("%d Cannot open '%s': %s\n",
 579                         ERROR + INTERNAL_ERROR, targ, strerror(errno));
 580                 return;
 581         }
 582         cprintf("%d %s\n", SEND_LISTING, targ);
 583
 584         while (client_getln(buf, sizeof buf), strcmp(buf, "000")) {
 585                 fprintf(mfp, "%s\n", buf);
 586         }
 587
 588         fclose(mfp);
 589 }
 590
 591
 592 /* Don't show the names of private rooms unless the viewing
 593  * user also knows the rooms.
 594  */
 595 void GenerateRoomDisplay(char *real_room,
 596                         struct CitContext *viewed,
 597                         struct CitContext *viewer) {
 598
 599         int ra;
 600
 601         strcpy(real_room, viewed->room.QRname);
 602         if (viewed->room.QRflags & QR_MAILBOX) {
 603                 strcpy(real_room, &real_room[11]);
 604         }
 605         if (viewed->room.QRflags & QR_PRIVATE) {
 606                 CtdlRoomAccess(&viewed->room, &viewer->user, &ra, NULL);
 607                 if ( (ra & UA_KNOWN) == 0) {
 608                         strcpy(real_room, "<private room>");
 609                 }
 610         }
 611
 612         if (viewed->cs_flags & CS_CHAT) {
 613                 while (strlen(real_room) < 14)
 614                         strcat(real_room, " ");
 615
 616                 strcpy(&real_room[14], "<chat>");
 617         }
 618
 619 }
 620
 621 /*
 622  * Convenience function.
 623  */
 624 int CtdlAccessCheck(int required_level) {
 625
 626         if (CC->internal_pgm) return(0);
 627         if (required_level >= ac_internal) {
 628                 cprintf("%d This is not a user-level command.\n",
 629                         ERROR + HIGHER_ACCESS_REQUIRED);
 630                 return(-1);
 631         }
 632
 633         if ((required_level >= ac_logged_in) && (CC->logged_in == 0)) {
 634                 cprintf("%d Not logged in.\n", ERROR + NOT_LOGGED_IN);
 635                 return(-1);
 636         }
 637
 638         if (CC->user.axlevel >= 6) return(0);
 639         if (required_level >= ac_aide) {
 640                 cprintf("%d This command requires Aide access.\n",
 641                         ERROR + HIGHER_ACCESS_REQUIRED);
 642                 return(-1);
 643         }
 644
 645         if (is_room_aide()) return(0);
 646         if (required_level >= ac_room_aide) {
 647                 cprintf("%d This command requires Aide or Room Aide access.\n",
 648                         ERROR + HIGHER_ACCESS_REQUIRED);
 649                 return(-1);
 650         }
 651
 652         /* shhh ... succeed quietly */
 653         return(0);
 654 }
 655
 656
 657
 658 /*
 659  * Terminate another running session
 660  */
 661 void cmd_term(char *cmdbuf)
 662 {
 663         int session_num;
 664         struct CitContext *ccptr;
 665         int found_it = 0;
 666         int allowed = 0;
 667
 668         session_num = extract_int(cmdbuf, 0);
 669         if (session_num == CC->cs_pid) {
 670                 cprintf("%d You can't kill your own session.\n", ERROR + ILLEGAL_VALUE);
 671                 return;
 672         }
 673
 674         lprintf(CTDL_DEBUG, "Locating session to kill\n");
 675         begin_critical_section(S_SESSION_TABLE);
 676         for (ccptr = ContextList; ccptr != NULL; ccptr = ccptr->next) {
 677                 if (session_num == ccptr->cs_pid) {
 678                         found_it = 1;
 679                         if ((ccptr->user.usernum == CC->user.usernum)
 680                            || (CC->user.axlevel >= 6)) {
 681                                 allowed = 1;
 682                                 ccptr->kill_me = 1;
 683                         }
 684                         else {
 685                                 allowed = 0;
 686                         }
 687                 }
 688         }
 689         end_critical_section(S_SESSION_TABLE);
 690
 691         if (found_it) {
 692                 if (allowed) {
 693                         cprintf("%d Session terminated.\n", CIT_OK);
 694                 }
 695                 else {
 696                         cprintf("%d You are not allowed to do that.\n",
 697                                 ERROR + HIGHER_ACCESS_REQUIRED);
 698                 }
 699         }
 700         else {
 701                 cprintf("%d No such session.\n", ERROR + ILLEGAL_VALUE);
 702         }
 703 }
 704
 705
 706
 707
 708
 709 /*
 710  * get the paginator prompt
 711  */
 712 void cmd_more(void) {
 713         cprintf("%d %s\n", CIT_OK, config.c_moreprompt);
 714 }
 715
 716 /*
 717  * echo
 718  */
 719 void cmd_echo(char *etext)
 720 {
 721         cprintf("%d %s\n", CIT_OK, etext);
 722 }
 723
 724
 725
 726 /*
 727  * identify as internal program
 728  */
 729 void cmd_ipgm(char *argbuf)
 730 {
 731         int secret;
 732
 733         secret = extract_int(argbuf, 0);
 734
 735         /* For security reasons, we do NOT allow this command to run
 736          * over the network.  Local sockets only.
 737          */
 738         if (!CC->is_local_socket) {
 739                 sleep(5);
 740                 cprintf("%d Authentication failed.\n",
 741                         ERROR + PASSWORD_REQUIRED);
 742         }
 743         else if (secret == config.c_ipgm_secret) {
 744                 CC->internal_pgm = 1;
 745                 strcpy(CC->curr_user, "<internal program>");
 746                 CC->cs_flags = CC->cs_flags|CS_STEALTH;
 747                 cprintf("%d Authenticated as an internal program.\n", CIT_OK);
 748         }
 749         else {
 750                 sleep(5);
 751                 cprintf("%d Authentication failed.\n",
 752                         ERROR + PASSWORD_REQUIRED);
 753                 lprintf(CTDL_ERR, "Warning: ipgm authentication failed.\n");
 754                 CC->kill_me = 1;
 755         }
 756
 757         /* Now change the ipgm secret for the next round.
 758          * (Disabled because it breaks concurrent scripts.  The fact that
 759          * we no longer accept IPGM over the network should be sufficient
 760          * to prevent brute-force attacks.  If you don't agree, uncomment
 761          * this block.)
 762         get_config();
 763         config.c_ipgm_secret = rand();
 764         put_config();
 765         */
 766 }
 767
 768
 769 /*
 770  * Shut down the server
 771  */
 772 void cmd_down(void) {
 773
 774         if (CtdlAccessCheck(ac_aide)) return;
 775
 776         cprintf("%d Shutting down server.  Goodbye.\n", CIT_OK);
 777         time_to_die = 1;
 778 }
 779
 780 /*
 781  * Halt the server without exiting the server process.
 782  */
 783 void cmd_halt(void) {
 784
 785         if (CtdlAccessCheck(ac_aide)) return;
 786
 787         cprintf("%d Halting server.  Goodbye.\n", CIT_OK);
 788         time_to_die = 1;
 789         shutdown_and_halt = 1;
 790 }
 791
 792 /*
 793  * Schedule or cancel a server shutdown
 794  */
 795 void cmd_scdn(char *argbuf)
 796 {
 797         int new_state;
 798
 799         if (CtdlAccessCheck(ac_aide)) return;
 800
 801         new_state = extract_int(argbuf, 0);
 802         if ((new_state == 0) || (new_state == 1)) {
 803                 ScheduledShutdown = new_state;
 804         }
 805         cprintf("%d %d\n", CIT_OK, ScheduledShutdown);
 806 }
 807
 808
 809 /*
 810  * Set or unset asynchronous protocol mode
 811  */
 812 void cmd_asyn(char *argbuf)
 813 {
 814         int new_state;
 815
 816         new_state = extract_int(argbuf, 0);
 817         if ((new_state == 0) || (new_state == 1)) {
 818                 CC->is_async = new_state;
 819         }
 820         cprintf("%d %d\n", CIT_OK, CC->is_async);
 821 }
 822
 823
 824 /*
 825  * Generate a "nonce" for APOP-style authentication.
 826  *
 827  * RFC 1725 et al specify a PID to be placed in front of the nonce.
 828  * Quoth BTX: That would be stupid.
 829  */
 830 void generate_nonce(struct CitContext *con) {
 831         struct timeval tv;
 832
 833         memset(con->cs_nonce, NONCE_SIZE, 0);
 834         gettimeofday(&tv, NULL);
 835         memset(con->cs_nonce, NONCE_SIZE, 0);
 836         snprintf(con->cs_nonce, NONCE_SIZE, "<%d%ld@%s>",
 837                 rand(), (long)tv.tv_usec, config.c_fqdn);
 838 }
 839
 840
 841
 842
 843 /*
 844  * Back-end function for starting a session
 845  */
 846 void begin_session(struct CitContext *con)
 847 {
 848         socklen_t len;
 849         struct sockaddr_in sin;
 850
 851         /*
 852          * Initialize some variables specific to our context.
 853          */
 854         con->logged_in = 0;
 855         con->internal_pgm = 0;
 856         con->download_fp = NULL;
 857         con->upload_fp = NULL;
 858         con->FirstExpressMessage = NULL;
 859         time(&con->lastcmd);
 860         time(&con->lastidle);
 861         strcpy(con->lastcmdname, "    ");
 862         strcpy(con->cs_clientname, "(unknown)");
 863         strcpy(con->curr_user, NLI);
 864         strcpy(con->net_node, "");
 865         strcpy(con->fake_username, "");
 866         strcpy(con->fake_postname, "");
 867         strcpy(con->fake_hostname, "");
 868         strcpy(con->fake_roomname, "");
 869         generate_nonce(con);
 870         safestrncpy(con->cs_host, config.c_fqdn, sizeof con->cs_host);
 871         safestrncpy(con->cs_addr, "", sizeof con->cs_addr);
 872         con->cs_host[sizeof con->cs_host - 1] = 0;
 873         len = sizeof sin;
 874         if (!CC->is_local_socket) {
 875                 if (!getpeername(con->client_socket, (struct sockaddr *) &sin, &len)) {
 876                         locate_host(con->cs_host, sizeof con->cs_host,
 877                                 con->cs_addr, sizeof con->cs_addr,
 878                                 &sin.sin_addr
 879                         );
 880                 }
 881         }
 882         else {
 883                 strcpy(con->cs_host, "");
 884         }
 885         con->cs_flags = 0;
 886         con->upload_type = UPL_FILE;
 887         con->dl_is_net = 0;
 888
 889         con->nologin = 0;
 890         if ((config.c_maxsessions > 0)&&(num_sessions > config.c_maxsessions))
 891                 con->nologin = 1;
 892
 893         lprintf(CTDL_NOTICE, "Session started.\n");
 894
 895         /* Run any session startup routines registered by loadable modules */
 896         PerformSessionHooks(EVT_START);
 897 }
 898
 899
 900 void citproto_begin_session() {
 901         if (CC->nologin==1) {
 902                 cprintf("%d %s: Too many users are already online "
 903                         "(maximum is %d)\n",
 904                         ERROR + MAX_SESSIONS_EXCEEDED,
 905                         config.c_nodename, config.c_maxsessions);
 906         }
 907         else {
 908                 cprintf("%d %s Citadel server ready.\n",
 909                         CIT_OK, config.c_nodename);
 910         }
 911 }
 912
 913
 914
 915
 916 /*
 917  * This loop recognizes all server commands.
 918  */
 919 void do_command_loop(void) {
 920         char cmdbuf[SIZ];
 921
 922         time(&CC->lastcmd);
 923         memset(cmdbuf, 0, sizeof cmdbuf); /* Clear it, just in case */
 924         if (client_getln(cmdbuf, sizeof cmdbuf) < 1) {
 925                 lprintf(CTDL_ERR, "Client disconnected: ending session.\n");
 926                 CC->kill_me = 1;
 927                 return;
 928         }
 929
 930         /* Log the server command, but don't show passwords... */
 931         if ( (strncasecmp(cmdbuf, "PASS", 4))
 932            && (strncasecmp(cmdbuf, "SETP", 4)) ) {
 933                 lprintf(CTDL_INFO, "%s\n", cmdbuf);
 934         }
 935         else {
 936                 lprintf(CTDL_INFO, "<password command sent>\n");
 937         }
 938
 939         buffer_output();
 940
 941         /*
 942          * Let other clients see the last command we executed, and
 943          * update the idle time, but not NOOP, QNOP, PEXP, GEXP, RWHO, or TIME.
 944          */
 945         if ( (strncasecmp(cmdbuf, "NOOP", 4))
 946            && (strncasecmp(cmdbuf, "QNOP", 4))
 947            && (strncasecmp(cmdbuf, "PEXP", 4))
 948            && (strncasecmp(cmdbuf, "GEXP", 4))
 949            && (strncasecmp(cmdbuf, "RWHO", 4))
 950            && (strncasecmp(cmdbuf, "TIME", 4)) ) {
 951                 strcpy(CC->lastcmdname, "    ");
 952                 safestrncpy(CC->lastcmdname, cmdbuf, sizeof(CC->lastcmdname));
 953                 time(&CC->lastidle);
 954         }
 955
 956         if ((strncasecmp(cmdbuf, "ENT0", 4))
 957            && (strncasecmp(cmdbuf, "MESG", 4))
 958            && (strncasecmp(cmdbuf, "MSGS", 4)))
 959         {
 960            CC->cs_flags &= ~CS_POSTING;
 961         }
 962
 963         if (!strncasecmp(cmdbuf, "NOOP", 4)) {
 964                 cprintf("%d%cok\n", CIT_OK, CtdlCheckExpress() );
 965         }
 966
 967         else if (!strncasecmp(cmdbuf, "QNOP", 4)) {
 968                 /* do nothing, this command returns no response */
 969         }
 970
 971         else if (!strncasecmp(cmdbuf,"QUIT",4)) {
 972                 cprintf("%d Goodbye.\n", CIT_OK);
 973                 CC->kill_me = 1;
 974         }
 975
 976         else if (!strncasecmp(cmdbuf,"ASYN",4)) {
 977                 cmd_asyn(&cmdbuf[5]);
 978         }
 979
 980         else if (!strncasecmp(cmdbuf,"LOUT",4)) {
 981                 if (CC->logged_in) logout(CC);
 982                 cprintf("%d logged out.\n", CIT_OK);
 983         }
 984
 985         else if (!strncasecmp(cmdbuf,"USER",4)) {
 986                 cmd_user(&cmdbuf[5]);
 987         }
 988
 989         else if (!strncasecmp(cmdbuf,"PASS",4)) {
 990                 cmd_pass(&cmdbuf[5]);
 991         }
 992
 993         else if (!strncasecmp(cmdbuf,"NEWU",4)) {
 994                 cmd_newu(&cmdbuf[5]);
 995         }
 996
 997         else if (!strncasecmp(cmdbuf,"CREU",4)) {
 998                 cmd_creu(&cmdbuf[5]);
 999         }
1000
1001         else if (!strncasecmp(cmdbuf,"SETP",4)) {
1002                 cmd_setp(&cmdbuf[5]);
1003         }
1004
1005         else if (!strncasecmp(cmdbuf,"LRMS",4)) {
1006                 cmd_lrms(&cmdbuf[5]);
1007         }
1008
1009         else if (!strncasecmp(cmdbuf,"LKRA",4)) {
1010                 cmd_lkra(&cmdbuf[5]);
1011         }
1012
1013         else if (!strncasecmp(cmdbuf,"LKRN",4)) {
1014                 cmd_lkrn(&cmdbuf[5]);
1015         }
1016
1017         else if (!strncasecmp(cmdbuf,"LKRO",4)) {
1018                 cmd_lkro(&cmdbuf[5]);
1019         }
1020
1021         else if (!strncasecmp(cmdbuf,"LZRM",4)) {
1022                 cmd_lzrm(&cmdbuf[5]);
1023         }
1024
1025         else if (!strncasecmp(cmdbuf,"LPRM",4)) {
1026                 cmd_lprm(&cmdbuf[5]);
1027         }
1028
1029         else if (!strncasecmp(cmdbuf,"GETU",4)) {
1030                 cmd_getu();
1031         }
1032
1033         else if (!strncasecmp(cmdbuf,"SETU",4)) {
1034                 cmd_setu(&cmdbuf[5]);
1035         }
1036
1037         else if (!strncasecmp(cmdbuf,"GOTO",4)) {
1038                 cmd_goto(&cmdbuf[5]);
1039         }
1040
1041         else if (!strncasecmp(cmdbuf,"MSGS",4)) {
1042                 cmd_msgs(&cmdbuf[5]);
1043         }
1044
1045         else if (!strncasecmp(cmdbuf,"WHOK",4)) {
1046                 cmd_whok();
1047         }
1048
1049         else if (!strncasecmp(cmdbuf,"RDIR",4)) {
1050                 cmd_rdir();
1051         }
1052
1053         else if (!strncasecmp(cmdbuf,"EUID",4)) {
1054                 cmd_euid(&cmdbuf[5]);
1055         }
1056
1057         else if (!strncasecmp(cmdbuf,"MSG0",4)) {
1058                 cmd_msg0(&cmdbuf[5]);
1059         }
1060
1061         else if (!strncasecmp(cmdbuf,"MSG2",4)) {
1062                 cmd_msg2(&cmdbuf[5]);
1063         }
1064
1065         else if (!strncasecmp(cmdbuf,"MSG3",4)) {
1066                 cmd_msg3(&cmdbuf[5]);
1067         }
1068
1069         else if (!strncasecmp(cmdbuf,"MSG4",4)) {
1070                 cmd_msg4(&cmdbuf[5]);
1071         }
1072
1073         else if (!strncasecmp(cmdbuf,"MSGP",4)) {
1074                 cmd_msgp(&cmdbuf[5]);
1075         }
1076
1077         else if (!strncasecmp(cmdbuf,"OPNA",4)) {
1078                 cmd_opna(&cmdbuf[5]);
1079         }
1080
1081         else if (!strncasecmp(cmdbuf,"DLAT",4)) {
1082                 cmd_dlat(&cmdbuf[5]);
1083         }
1084
1085         else if (!strncasecmp(cmdbuf,"INFO",4)) {
1086                 cmd_info();
1087         }
1088
1089         else if (!strncasecmp(cmdbuf,"SLRP",4)) {
1090                 cmd_slrp(&cmdbuf[5]);
1091         }
1092
1093         else if (!strncasecmp(cmdbuf,"INVT",4)) {
1094                 cmd_invt_kick(&cmdbuf[5],1);
1095         }
1096
1097         else if (!strncasecmp(cmdbuf,"KICK",4)) {
1098                 cmd_invt_kick(&cmdbuf[5],0);
1099         }
1100
1101         else if (!strncasecmp(cmdbuf,"GETR",4)) {
1102                 cmd_getr();
1103         }
1104
1105         else if (!strncasecmp(cmdbuf,"SETR",4)) {
1106                 cmd_setr(&cmdbuf[5]);
1107         }
1108
1109         else if (!strncasecmp(cmdbuf,"GETA",4)) {
1110                 cmd_geta();
1111         }
1112
1113         else if (!strncasecmp(cmdbuf,"SETA",4)) {
1114                 cmd_seta(&cmdbuf[5]);
1115         }
1116
1117         else if (!strncasecmp(cmdbuf,"ENT0",4)) {
1118                 cmd_ent0(&cmdbuf[5]);
1119         }
1120
1121         else if (!strncasecmp(cmdbuf,"RINF",4)) {
1122                 cmd_rinf();
1123         }
1124
1125         else if (!strncasecmp(cmdbuf,"DELE",4)) {
1126                 cmd_dele(&cmdbuf[5]);
1127         }
1128
1129         else if (!strncasecmp(cmdbuf,"KILL",4)) {
1130                 cmd_kill(&cmdbuf[5]);
1131         }
1132
1133         else if (!strncasecmp(cmdbuf,"CRE8",4)) {
1134                 cmd_cre8(&cmdbuf[5]);
1135         }
1136
1137         else if (!strncasecmp(cmdbuf,"MOVE",4)) {
1138                 cmd_move(&cmdbuf[5]);
1139         }
1140
1141         else if (!strncasecmp(cmdbuf,"FORG",4)) {
1142                 cmd_forg();
1143         }
1144
1145         else if (!strncasecmp(cmdbuf,"MESG",4)) {
1146                 cmd_mesg(&cmdbuf[5]);
1147         }
1148
1149         else if (!strncasecmp(cmdbuf,"EMSG",4)) {
1150                 cmd_emsg(&cmdbuf[5]);
1151         }
1152
1153         else if (!strncasecmp(cmdbuf,"GNUR",4)) {
1154                 cmd_gnur();
1155         }
1156
1157         else if (!strncasecmp(cmdbuf,"VALI",4)) {
1158                 cmd_vali(&cmdbuf[5]);
1159         }
1160
1161         else if (!strncasecmp(cmdbuf,"EINF",4)) {
1162                 cmd_einf(&cmdbuf[5]);
1163         }
1164
1165         else if (!strncasecmp(cmdbuf,"LIST",4)) {
1166                 cmd_list(&cmdbuf[5]);
1167         }
1168
1169         else if (!strncasecmp(cmdbuf,"CHEK",4)) {
1170                 cmd_chek();
1171         }
1172
1173         else if (!strncasecmp(cmdbuf,"DELF",4)) {
1174                 cmd_delf(&cmdbuf[5]);
1175         }
1176
1177         else if (!strncasecmp(cmdbuf,"MOVF",4)) {
1178                 cmd_movf(&cmdbuf[5]);
1179         }
1180
1181         else if (!strncasecmp(cmdbuf,"NETF",4)) {
1182                 cmd_netf(&cmdbuf[5]);
1183         }
1184
1185         else if (!strncasecmp(cmdbuf,"OPEN",4)) {
1186                 cmd_open(&cmdbuf[5]);
1187         }
1188
1189         else if (!strncasecmp(cmdbuf,"CLOS",4)) {
1190                 cmd_clos();
1191         }
1192
1193         else if (!strncasecmp(cmdbuf,"UOPN",4)) {
1194                 cmd_uopn(&cmdbuf[5]);
1195         }
1196
1197         else if (!strncasecmp(cmdbuf,"UCLS",4)) {
1198                 cmd_ucls(&cmdbuf[5]);
1199         }
1200
1201         else if (!strncasecmp(cmdbuf,"READ",4)) {
1202                 cmd_read(&cmdbuf[5]);
1203         }
1204
1205         else if (!strncasecmp(cmdbuf,"WRIT",4)) {
1206                 cmd_writ(&cmdbuf[5]);
1207         }
1208
1209         else if (!strncasecmp(cmdbuf,"QUSR",4)) {
1210                 cmd_qusr(&cmdbuf[5]);
1211         }
1212
1213         else if (!strncasecmp(cmdbuf,"ECHO",4)) {
1214                 cmd_echo(&cmdbuf[5]);
1215         }
1216
1217         else if (!strncasecmp(cmdbuf,"OIMG",4)) {
1218                 cmd_oimg(&cmdbuf[5]);
1219         }
1220
1221         else if (!strncasecmp(cmdbuf,"MORE",4)) {
1222                 cmd_more();
1223         }
1224
1225         else if (!strncasecmp(cmdbuf,"NDOP",4)) {
1226                 cmd_ndop(&cmdbuf[5]);
1227         }
1228
1229         else if (!strncasecmp(cmdbuf,"NUOP",4)) {
1230                 cmd_nuop(&cmdbuf[5]);
1231         }
1232
1233         else if (!strncasecmp(cmdbuf,"LFLR",4)) {
1234                 cmd_lflr();
1235         }
1236
1237         else if (!strncasecmp(cmdbuf,"CFLR",4)) {
1238                 cmd_cflr(&cmdbuf[5]);
1239         }
1240
1241         else if (!strncasecmp(cmdbuf,"KFLR",4)) {
1242                 cmd_kflr(&cmdbuf[5]);
1243         }
1244
1245         else if (!strncasecmp(cmdbuf,"EFLR",4)) {
1246                 cmd_eflr(&cmdbuf[5]);
1247         }
1248
1249         else if (!strncasecmp(cmdbuf,"IDEN",4)) {
1250                 cmd_iden(&cmdbuf[5]);
1251         }
1252
1253         else if (!strncasecmp(cmdbuf,"IPGM",4)) {
1254                 cmd_ipgm(&cmdbuf[5]);
1255         }
1256
1257         else if (!strncasecmp(cmdbuf,"TERM",4)) {
1258                 cmd_term(&cmdbuf[5]);
1259         }
1260
1261         else if (!strncasecmp(cmdbuf,"DOWN",4)) {
1262                 cmd_down();
1263         }
1264
1265         else if (!strncasecmp(cmdbuf,"HALT",4)) {
1266                 cmd_halt();
1267         }
1268
1269         else if (!strncasecmp(cmdbuf,"SCDN",4)) {
1270                 cmd_scdn(&cmdbuf[5]);
1271         }
1272
1273         else if (!strncasecmp(cmdbuf, "UIMG", 4)) {
1274                 cmd_uimg(&cmdbuf[5]);
1275         }
1276
1277         else if (!strncasecmp(cmdbuf, "TIME", 4)) {
1278                 cmd_time();
1279         }
1280
1281         else if (!strncasecmp(cmdbuf, "AGUP", 4)) {
1282                 cmd_agup(&cmdbuf[5]);
1283         }
1284
1285         else if (!strncasecmp(cmdbuf, "ASUP", 4)) {
1286                 cmd_asup(&cmdbuf[5]);
1287         }
1288
1289         else if (!strncasecmp(cmdbuf, "GPEX", 4)) {
1290                 cmd_gpex(&cmdbuf[5]);
1291         }
1292
1293         else if (!strncasecmp(cmdbuf, "SPEX", 4)) {
1294                 cmd_spex(&cmdbuf[5]);
1295         }
1296
1297         else if (!strncasecmp(cmdbuf, "CONF", 4)) {
1298                 cmd_conf(&cmdbuf[5]);
1299         }
1300
1301         else if (!strncasecmp(cmdbuf, "SEEN", 4)) {
1302                 cmd_seen(&cmdbuf[5]);
1303         }
1304
1305         else if (!strncasecmp(cmdbuf, "GTSN", 4)) {
1306                 cmd_gtsn(&cmdbuf[5]);
1307         }
1308
1309         else if (!strncasecmp(cmdbuf, "VIEW", 4)) {
1310                 cmd_view(&cmdbuf[5]);
1311         }
1312
1313         else if (!strncasecmp(cmdbuf, "ISME", 4)) {
1314                 cmd_isme(&cmdbuf[5]);
1315         }
1316
1317         else if (!DLoader_Exec_Cmd(cmdbuf)) {
1318                 cprintf("%d Unrecognized or unsupported command.\n",
1319                         ERROR + CMD_NOT_SUPPORTED);
1320                }
1321
1322         unbuffer_output();
1323
1324         /* Run any after-each-command routines registered by modules */
1325         PerformSessionHooks(EVT_CMD);
1326 }
1327
1328
1329 /*
1330  * This loop performs all asynchronous functions.
1331  */
1332 void do_async_loop(void) {
1333         PerformSessionHooks(EVT_ASYNC);
1334 }