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, addrbuf);
 370                                 }
 371                         }
 372                 }
 373                 fclose(fp);
 374                 pc_timestamp = time(NULL);
 375                 end_critical_section(S_PUBLIC_CLIENTS);
 376         }
 377
 378         lprintf(CTDL_DEBUG, "Checking whether %s is a local or public client\n",
 379                 CC->cs_addr);
 380         for (i=0; i<num_parms(public_clients); ++i) {
 381                 extract_token(addrbuf, public_clients, i, '|', sizeof addrbuf);
 382                 if (!strcasecmp(CC->cs_addr, addrbuf)) {
 383                         lprintf(CTDL_DEBUG, "... yes it is.\n");
 384                         return(1);
 385                 }
 386         }
 387
 388         /* No hits.  This is not a public client. */
 389         lprintf(CTDL_DEBUG, "... no it isn't.\n");
 390         return(0);
 391 }
 392
 393
 394 /*
 395  * the client is identifying itself to the server
 396  */
 397 void cmd_iden(char *argbuf)
 398 {
 399         int dev_code;
 400         int cli_code;
 401         int rev_level;
 402         char desc[128];
 403         char from_host[128];
 404         struct in_addr addr;
 405         int do_lookup = 0;
 406
 407         if (num_parms(argbuf)<4) {
 408                 cprintf("%d usage error\n", ERROR + ILLEGAL_VALUE);
 409                 return;
 410         }
 411
 412         dev_code = extract_int(argbuf,0);
 413         cli_code = extract_int(argbuf,1);
 414         rev_level = extract_int(argbuf,2);
 415         extract_token(desc, argbuf, 3, '|', sizeof desc);
 416
 417         safestrncpy(from_host, config.c_fqdn, sizeof from_host);
 418         from_host[sizeof from_host - 1] = 0;
 419         if (num_parms(argbuf)>=5) extract_token(from_host, argbuf, 4, '|', sizeof from_host);
 420
 421         CC->cs_clientdev = dev_code;
 422         CC->cs_clienttyp = cli_code;
 423         CC->cs_clientver = rev_level;
 424         safestrncpy(CC->cs_clientname, desc, sizeof CC->cs_clientname);
 425         CC->cs_clientname[31] = 0;
 426
 427         if (strlen(from_host) > 0) {
 428                 if (CC->is_local_socket) do_lookup = 1;
 429                 else if (is_public_client()) do_lookup = 1;
 430         }
 431
 432         if (do_lookup) {
 433                 lprintf(CTDL_DEBUG, "Looking up hostname '%s'\n", from_host);
 434                 if ((addr.s_addr = inet_addr(from_host)) != -1) {
 435                         locate_host(CC->cs_host, sizeof CC->cs_host,
 436                                 NULL, 0,
 437                                 &addr);
 438                 }
 439                 else {
 440                         safestrncpy(CC->cs_host, from_host, sizeof CC->cs_host);
 441                         CC->cs_host[sizeof CC->cs_host - 1] = 0;
 442                 }
 443         }
 444
 445         lprintf(CTDL_NOTICE, "Client %d/%d/%01d.%02d (%s) from %s\n",
 446                 dev_code,
 447                 cli_code,
 448                 (rev_level / 100),
 449                 (rev_level % 100),
 450                 desc,
 451                 CC->cs_host);
 452         cprintf("%d Ok\n",CIT_OK);
 453 }
 454
 455
 456 /*
 457  * display system messages or help
 458  */
 459 void cmd_mesg(char *mname)
 460 {
 461         FILE *mfp;
 462         char targ[256];
 463         char buf[256];
 464         char buf2[256];
 465         char *dirs[2];
 466         DIR *dp;
 467         struct dirent *d;
 468
 469         extract_token(buf, mname, 0, '|', sizeof buf);
 470
 471         dirs[0] = strdup(ctdl_message_dir);
 472         dirs[1] = strdup(ctdl_hlp_dir);
 473
 474         snprintf(buf2, sizeof buf2, "%s.%d.%d",
 475                 buf, CC->cs_clientdev, CC->cs_clienttyp);
 476
 477         /* If the client requested "?" then produce a listing */
 478         if (!strcmp(buf, "?")) {
 479                 cprintf("%d %s\n", LISTING_FOLLOWS, buf);
 480                 dp = opendir(dirs[1]);
 481                 if (dp != NULL) {
 482                         while (d = readdir(dp), d != NULL) {
 483                                 if (d->d_name[0] != '.') {
 484                                         cprintf(" %s\n", d->d_name);
 485                                 }
 486                         }
 487                         closedir(dp);
 488                 }
 489                 cprintf("000\n");
 490                 free(dirs[0]);
 491                 free(dirs[1]);
 492                 return;
 493         }
 494
 495         /* Otherwise, look for the requested file by name. */
 496         else {
 497                 mesg_locate(targ, sizeof targ, buf2, 2, (const char **)dirs);
 498                 if (strlen(targ) == 0) {
 499                         snprintf(buf2, sizeof buf2, "%s.%d",
 500                                                         buf, CC->cs_clientdev);
 501                         mesg_locate(targ, sizeof targ, buf2, 2,
 502                                                         (const char **)dirs);
 503                         if (strlen(targ) == 0) {
 504                                 mesg_locate(targ, sizeof targ, buf, 2,
 505                                                         (const char **)dirs);
 506                         }
 507                 }
 508         }
 509
 510         free(dirs[0]);
 511         free(dirs[1]);
 512
 513         if (strlen(targ)==0) {
 514                 cprintf("%d '%s' not found.  (Searching in %s and %s)\n",
 515                         ERROR + FILE_NOT_FOUND,
 516                         mname,
 517                         ctdl_message_dir,
 518                         ctdl_hlp_dir
 519                 );
 520                 return;
 521         }
 522
 523         mfp = fopen(targ, "r");
 524         if (mfp==NULL) {
 525                 cprintf("%d Cannot open '%s': %s\n",
 526                         ERROR + INTERNAL_ERROR, targ, strerror(errno));
 527                 return;
 528         }
 529         cprintf("%d %s\n", LISTING_FOLLOWS,buf);
 530
 531         while (fgets(buf, (sizeof buf - 1), mfp) != NULL) {
 532                 buf[strlen(buf)-1] = 0;
 533                 do_help_subst(buf);
 534                 cprintf("%s\n",buf);
 535         }
 536
 537         fclose(mfp);
 538         cprintf("000\n");
 539 }
 540
 541
 542 /*
 543  * enter system messages or help
 544  */
 545 void cmd_emsg(char *mname)
 546 {
 547         FILE *mfp;
 548         char targ[256];
 549         char buf[256];
 550         char *dirs[2];
 551         int a;
 552
 553         unbuffer_output();
 554
 555         if (CtdlAccessCheck(ac_aide)) return;
 556
 557         extract_token(buf, mname, 0, '|', sizeof buf);
 558         for (a=0; a<strlen(buf); ++a) {         /* security measure */
 559                 if (buf[a] == '/') buf[a] = '.';
 560         }
 561
 562         dirs[0] = strdup(ctdl_message_dir);
 563         dirs[1] = strdup(ctdl_hlp_dir);
 564
 565         mesg_locate(targ, sizeof targ, buf, 2, (const char**)dirs);
 566         free(dirs[0]);
 567         free(dirs[1]);
 568
 569         if (strlen(targ)==0) {
 570                 snprintf(targ, sizeof targ,
 571                                  "%s/%s",
 572                                  ctdl_hlp_dir, 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  * Halt the server without exiting the server process.
 781  */
 782 void cmd_halt(void) {
 783
 784         if (CtdlAccessCheck(ac_aide)) return;
 785
 786         cprintf("%d Halting server.  Goodbye.\n", CIT_OK);
 787         time_to_die = 1;
 788         shutdown_and_halt = 1;
 789 }
 790
 791 /*
 792  * Schedule or cancel a server shutdown
 793  */
 794 void cmd_scdn(char *argbuf)
 795 {
 796         int new_state;
 797
 798         if (CtdlAccessCheck(ac_aide)) return;
 799
 800         new_state = extract_int(argbuf, 0);
 801         if ((new_state == 0) || (new_state == 1)) {
 802                 ScheduledShutdown = new_state;
 803         }
 804         cprintf("%d %d\n", CIT_OK, ScheduledShutdown);
 805 }
 806
 807
 808 /*
 809  * Set or unset asynchronous protocol mode
 810  */
 811 void cmd_asyn(char *argbuf)
 812 {
 813         int new_state;
 814
 815         new_state = extract_int(argbuf, 0);
 816         if ((new_state == 0) || (new_state == 1)) {
 817                 CC->is_async = new_state;
 818         }
 819         cprintf("%d %d\n", CIT_OK, CC->is_async);
 820 }
 821
 822
 823 /*
 824  * Generate a "nonce" for APOP-style authentication.
 825  *
 826  * RFC 1725 et al specify a PID to be placed in front of the nonce.
 827  * Quoth BTX: That would be stupid.
 828  */
 829 void generate_nonce(struct CitContext *con) {
 830         struct timeval tv;
 831
 832         memset(con->cs_nonce, NONCE_SIZE, 0);
 833         gettimeofday(&tv, NULL);
 834         memset(con->cs_nonce, NONCE_SIZE, 0);
 835         snprintf(con->cs_nonce, NONCE_SIZE, "<%d%ld@%s>",
 836                 rand(), (long)tv.tv_usec, config.c_fqdn);
 837 }
 838
 839
 840
 841
 842 /*
 843  * Back-end function for starting a session
 844  */
 845 void begin_session(struct CitContext *con)
 846 {
 847         socklen_t len;
 848         struct sockaddr_in sin;
 849
 850         /*
 851          * Initialize some variables specific to our context.
 852          */
 853         con->logged_in = 0;
 854         con->internal_pgm = 0;
 855         con->download_fp = NULL;
 856         con->upload_fp = NULL;
 857         con->FirstExpressMessage = NULL;
 858         time(&con->lastcmd);
 859         time(&con->lastidle);
 860         strcpy(con->lastcmdname, "    ");
 861         strcpy(con->cs_clientname, "(unknown)");
 862         strcpy(con->curr_user, NLI);
 863         strcpy(con->net_node, "");
 864         strcpy(con->fake_username, "");
 865         strcpy(con->fake_postname, "");
 866         strcpy(con->fake_hostname, "");
 867         strcpy(con->fake_roomname, "");
 868         generate_nonce(con);
 869         safestrncpy(con->cs_host, config.c_fqdn, sizeof con->cs_host);
 870         safestrncpy(con->cs_addr, "", sizeof con->cs_addr);
 871         con->cs_host[sizeof con->cs_host - 1] = 0;
 872         len = sizeof sin;
 873         if (!CC->is_local_socket) {
 874                 if (!getpeername(con->client_socket, (struct sockaddr *) &sin, &len)) {
 875                         locate_host(con->cs_host, sizeof con->cs_host,
 876                                 con->cs_addr, sizeof con->cs_addr,
 877                                 &sin.sin_addr
 878                         );
 879                 }
 880         }
 881         else {
 882                 strcpy(con->cs_host, "");
 883         }
 884         con->cs_flags = 0;
 885         con->upload_type = UPL_FILE;
 886         con->dl_is_net = 0;
 887
 888         con->nologin = 0;
 889         if ((config.c_maxsessions > 0)&&(num_sessions > config.c_maxsessions))
 890                 con->nologin = 1;
 891
 892         lprintf(CTDL_NOTICE, "Session started.\n");
 893
 894         /* Run any session startup routines registered by loadable modules */
 895         PerformSessionHooks(EVT_START);
 896 }
 897
 898
 899 void citproto_begin_session() {
 900         if (CC->nologin==1) {
 901                 cprintf("%d %s: Too many users are already online "
 902                         "(maximum is %d)\n",
 903                         ERROR + MAX_SESSIONS_EXCEEDED,
 904                         config.c_nodename, config.c_maxsessions);
 905         }
 906         else {
 907                 cprintf("%d %s Citadel server ready.\n",
 908                         CIT_OK, config.c_nodename);
 909         }
 910 }
 911
 912
 913
 914
 915 /*
 916  * This loop recognizes all server commands.
 917  */
 918 void do_command_loop(void) {
 919         char cmdbuf[SIZ];
 920
 921         time(&CC->lastcmd);
 922         memset(cmdbuf, 0, sizeof cmdbuf); /* Clear it, just in case */
 923         if (client_getln(cmdbuf, sizeof cmdbuf) < 1) {
 924                 lprintf(CTDL_ERR, "Client disconnected: ending session.\n");
 925                 CC->kill_me = 1;
 926                 return;
 927         }
 928
 929         /* Log the server command, but don't show passwords... */
 930         if ( (strncasecmp(cmdbuf, "PASS", 4))
 931            && (strncasecmp(cmdbuf, "SETP", 4)) ) {
 932                 lprintf(CTDL_INFO, "%s\n", cmdbuf);
 933         }
 934         else {
 935                 lprintf(CTDL_INFO, "<password command sent>\n");
 936         }
 937
 938         buffer_output();
 939
 940         /*
 941          * Let other clients see the last command we executed, and
 942          * update the idle time, but not NOOP, QNOP, PEXP, GEXP, RWHO, or TIME.
 943          */
 944         if ( (strncasecmp(cmdbuf, "NOOP", 4))
 945            && (strncasecmp(cmdbuf, "QNOP", 4))
 946            && (strncasecmp(cmdbuf, "PEXP", 4))
 947            && (strncasecmp(cmdbuf, "GEXP", 4))
 948            && (strncasecmp(cmdbuf, "RWHO", 4))
 949            && (strncasecmp(cmdbuf, "TIME", 4)) ) {
 950                 strcpy(CC->lastcmdname, "    ");
 951                 safestrncpy(CC->lastcmdname, cmdbuf, sizeof(CC->lastcmdname));
 952                 time(&CC->lastidle);
 953         }
 954
 955         if ((strncasecmp(cmdbuf, "ENT0", 4))
 956            && (strncasecmp(cmdbuf, "MESG", 4))
 957            && (strncasecmp(cmdbuf, "MSGS", 4)))
 958         {
 959            CC->cs_flags &= ~CS_POSTING;
 960         }
 961
 962         if (!strncasecmp(cmdbuf, "NOOP", 4)) {
 963                 cprintf("%d%cok\n", CIT_OK, CtdlCheckExpress() );
 964         }
 965
 966         else if (!strncasecmp(cmdbuf, "QNOP", 4)) {
 967                 /* do nothing, this command returns no response */
 968         }
 969
 970         else if (!strncasecmp(cmdbuf,"QUIT",4)) {
 971                 cprintf("%d Goodbye.\n", CIT_OK);
 972                 CC->kill_me = 1;
 973         }
 974
 975         else if (!strncasecmp(cmdbuf,"ASYN",4)) {
 976                 cmd_asyn(&cmdbuf[5]);
 977         }
 978
 979         else if (!strncasecmp(cmdbuf,"LOUT",4)) {
 980                 if (CC->logged_in) logout(CC);
 981                 cprintf("%d logged out.\n", CIT_OK);
 982         }
 983
 984         else if (!strncasecmp(cmdbuf,"USER",4)) {
 985                 cmd_user(&cmdbuf[5]);
 986         }
 987
 988         else if (!strncasecmp(cmdbuf,"PASS",4)) {
 989                 cmd_pass(&cmdbuf[5]);
 990         }
 991
 992         else if (!strncasecmp(cmdbuf,"NEWU",4)) {
 993                 cmd_newu(&cmdbuf[5]);
 994         }
 995
 996         else if (!strncasecmp(cmdbuf,"CREU",4)) {
 997                 cmd_creu(&cmdbuf[5]);
 998         }
 999
1000         else if (!strncasecmp(cmdbuf,"SETP",4)) {
1001                 cmd_setp(&cmdbuf[5]);
1002         }
1003
1004         else if (!strncasecmp(cmdbuf,"LRMS",4)) {
1005                 cmd_lrms(&cmdbuf[5]);
1006         }
1007
1008         else if (!strncasecmp(cmdbuf,"LKRA",4)) {
1009                 cmd_lkra(&cmdbuf[5]);
1010         }
1011
1012         else if (!strncasecmp(cmdbuf,"LKRN",4)) {
1013                 cmd_lkrn(&cmdbuf[5]);
1014         }
1015
1016         else if (!strncasecmp(cmdbuf,"LKRO",4)) {
1017                 cmd_lkro(&cmdbuf[5]);
1018         }
1019
1020         else if (!strncasecmp(cmdbuf,"LZRM",4)) {
1021                 cmd_lzrm(&cmdbuf[5]);
1022         }
1023
1024         else if (!strncasecmp(cmdbuf,"LPRM",4)) {
1025                 cmd_lprm(&cmdbuf[5]);
1026         }
1027
1028         else if (!strncasecmp(cmdbuf,"GETU",4)) {
1029                 cmd_getu();
1030         }
1031
1032         else if (!strncasecmp(cmdbuf,"SETU",4)) {
1033                 cmd_setu(&cmdbuf[5]);
1034         }
1035
1036         else if (!strncasecmp(cmdbuf,"GOTO",4)) {
1037                 cmd_goto(&cmdbuf[5]);
1038         }
1039
1040         else if (!strncasecmp(cmdbuf,"MSGS",4)) {
1041                 cmd_msgs(&cmdbuf[5]);
1042         }
1043
1044         else if (!strncasecmp(cmdbuf,"WHOK",4)) {
1045                 cmd_whok();
1046         }
1047
1048         else if (!strncasecmp(cmdbuf,"RDIR",4)) {
1049                 cmd_rdir();
1050         }
1051
1052         else if (!strncasecmp(cmdbuf,"EUID",4)) {
1053                 cmd_euid(&cmdbuf[5]);
1054         }
1055
1056         else if (!strncasecmp(cmdbuf,"MSG0",4)) {
1057                 cmd_msg0(&cmdbuf[5]);
1058         }
1059
1060         else if (!strncasecmp(cmdbuf,"MSG2",4)) {
1061                 cmd_msg2(&cmdbuf[5]);
1062         }
1063
1064         else if (!strncasecmp(cmdbuf,"MSG3",4)) {
1065                 cmd_msg3(&cmdbuf[5]);
1066         }
1067
1068         else if (!strncasecmp(cmdbuf,"MSG4",4)) {
1069                 cmd_msg4(&cmdbuf[5]);
1070         }
1071
1072         else if (!strncasecmp(cmdbuf,"MSGP",4)) {
1073                 cmd_msgp(&cmdbuf[5]);
1074         }
1075
1076         else if (!strncasecmp(cmdbuf,"OPNA",4)) {
1077                 cmd_opna(&cmdbuf[5]);
1078         }
1079
1080         else if (!strncasecmp(cmdbuf,"INFO",4)) {
1081                 cmd_info();
1082         }
1083
1084         else if (!strncasecmp(cmdbuf,"SLRP",4)) {
1085                 cmd_slrp(&cmdbuf[5]);
1086         }
1087
1088         else if (!strncasecmp(cmdbuf,"INVT",4)) {
1089                 cmd_invt_kick(&cmdbuf[5],1);
1090         }
1091
1092         else if (!strncasecmp(cmdbuf,"KICK",4)) {
1093                 cmd_invt_kick(&cmdbuf[5],0);
1094         }
1095
1096         else if (!strncasecmp(cmdbuf,"GETR",4)) {
1097                 cmd_getr();
1098         }
1099
1100         else if (!strncasecmp(cmdbuf,"SETR",4)) {
1101                 cmd_setr(&cmdbuf[5]);
1102         }
1103
1104         else if (!strncasecmp(cmdbuf,"GETA",4)) {
1105                 cmd_geta();
1106         }
1107
1108         else if (!strncasecmp(cmdbuf,"SETA",4)) {
1109                 cmd_seta(&cmdbuf[5]);
1110         }
1111
1112         else if (!strncasecmp(cmdbuf,"ENT0",4)) {
1113                 cmd_ent0(&cmdbuf[5]);
1114         }
1115
1116         else if (!strncasecmp(cmdbuf,"RINF",4)) {
1117                 cmd_rinf();
1118         }
1119
1120         else if (!strncasecmp(cmdbuf,"DELE",4)) {
1121                 cmd_dele(&cmdbuf[5]);
1122         }
1123
1124         else if (!strncasecmp(cmdbuf,"KILL",4)) {
1125                 cmd_kill(&cmdbuf[5]);
1126         }
1127
1128         else if (!strncasecmp(cmdbuf,"CRE8",4)) {
1129                 cmd_cre8(&cmdbuf[5]);
1130         }
1131
1132         else if (!strncasecmp(cmdbuf,"MOVE",4)) {
1133                 cmd_move(&cmdbuf[5]);
1134         }
1135
1136         else if (!strncasecmp(cmdbuf,"FORG",4)) {
1137                 cmd_forg();
1138         }
1139
1140         else if (!strncasecmp(cmdbuf,"MESG",4)) {
1141                 cmd_mesg(&cmdbuf[5]);
1142         }
1143
1144         else if (!strncasecmp(cmdbuf,"EMSG",4)) {
1145                 cmd_emsg(&cmdbuf[5]);
1146         }
1147
1148         else if (!strncasecmp(cmdbuf,"GNUR",4)) {
1149                 cmd_gnur();
1150         }
1151
1152         else if (!strncasecmp(cmdbuf,"VALI",4)) {
1153                 cmd_vali(&cmdbuf[5]);
1154         }
1155
1156         else if (!strncasecmp(cmdbuf,"EINF",4)) {
1157                 cmd_einf(&cmdbuf[5]);
1158         }
1159
1160         else if (!strncasecmp(cmdbuf,"LIST",4)) {
1161                 cmd_list(&cmdbuf[5]);
1162         }
1163
1164         else if (!strncasecmp(cmdbuf,"CHEK",4)) {
1165                 cmd_chek();
1166         }
1167
1168         else if (!strncasecmp(cmdbuf,"DELF",4)) {
1169                 cmd_delf(&cmdbuf[5]);
1170         }
1171
1172         else if (!strncasecmp(cmdbuf,"MOVF",4)) {
1173                 cmd_movf(&cmdbuf[5]);
1174         }
1175
1176         else if (!strncasecmp(cmdbuf,"NETF",4)) {
1177                 cmd_netf(&cmdbuf[5]);
1178         }
1179
1180         else if (!strncasecmp(cmdbuf,"OPEN",4)) {
1181                 cmd_open(&cmdbuf[5]);
1182         }
1183
1184         else if (!strncasecmp(cmdbuf,"CLOS",4)) {
1185                 cmd_clos();
1186         }
1187
1188         else if (!strncasecmp(cmdbuf,"UOPN",4)) {
1189                 cmd_uopn(&cmdbuf[5]);
1190         }
1191
1192         else if (!strncasecmp(cmdbuf,"UCLS",4)) {
1193                 cmd_ucls(&cmdbuf[5]);
1194         }
1195
1196         else if (!strncasecmp(cmdbuf,"READ",4)) {
1197                 cmd_read(&cmdbuf[5]);
1198         }
1199
1200         else if (!strncasecmp(cmdbuf,"WRIT",4)) {
1201                 cmd_writ(&cmdbuf[5]);
1202         }
1203
1204         else if (!strncasecmp(cmdbuf,"QUSR",4)) {
1205                 cmd_qusr(&cmdbuf[5]);
1206         }
1207
1208         else if (!strncasecmp(cmdbuf,"ECHO",4)) {
1209                 cmd_echo(&cmdbuf[5]);
1210         }
1211
1212         else if (!strncasecmp(cmdbuf,"OIMG",4)) {
1213                 cmd_oimg(&cmdbuf[5]);
1214         }
1215
1216         else if (!strncasecmp(cmdbuf,"MORE",4)) {
1217                 cmd_more();
1218         }
1219
1220         else if (!strncasecmp(cmdbuf,"NDOP",4)) {
1221                 cmd_ndop(&cmdbuf[5]);
1222         }
1223
1224         else if (!strncasecmp(cmdbuf,"NUOP",4)) {
1225                 cmd_nuop(&cmdbuf[5]);
1226         }
1227
1228         else if (!strncasecmp(cmdbuf,"LFLR",4)) {
1229                 cmd_lflr();
1230         }
1231
1232         else if (!strncasecmp(cmdbuf,"CFLR",4)) {
1233                 cmd_cflr(&cmdbuf[5]);
1234         }
1235
1236         else if (!strncasecmp(cmdbuf,"KFLR",4)) {
1237                 cmd_kflr(&cmdbuf[5]);
1238         }
1239
1240         else if (!strncasecmp(cmdbuf,"EFLR",4)) {
1241                 cmd_eflr(&cmdbuf[5]);
1242         }
1243
1244         else if (!strncasecmp(cmdbuf,"IDEN",4)) {
1245                 cmd_iden(&cmdbuf[5]);
1246         }
1247
1248         else if (!strncasecmp(cmdbuf,"IPGM",4)) {
1249                 cmd_ipgm(&cmdbuf[5]);
1250         }
1251
1252         else if (!strncasecmp(cmdbuf,"TERM",4)) {
1253                 cmd_term(&cmdbuf[5]);
1254         }
1255
1256         else if (!strncasecmp(cmdbuf,"DOWN",4)) {
1257                 cmd_down();
1258         }
1259
1260         else if (!strncasecmp(cmdbuf,"HALT",4)) {
1261                 cmd_halt();
1262         }
1263
1264         else if (!strncasecmp(cmdbuf,"SCDN",4)) {
1265                 cmd_scdn(&cmdbuf[5]);
1266         }
1267
1268         else if (!strncasecmp(cmdbuf, "UIMG", 4)) {
1269                 cmd_uimg(&cmdbuf[5]);
1270         }
1271
1272         else if (!strncasecmp(cmdbuf, "TIME", 4)) {
1273                 cmd_time();
1274         }
1275
1276         else if (!strncasecmp(cmdbuf, "AGUP", 4)) {
1277                 cmd_agup(&cmdbuf[5]);
1278         }
1279
1280         else if (!strncasecmp(cmdbuf, "ASUP", 4)) {
1281                 cmd_asup(&cmdbuf[5]);
1282         }
1283
1284         else if (!strncasecmp(cmdbuf, "GPEX", 4)) {
1285                 cmd_gpex(&cmdbuf[5]);
1286         }
1287
1288         else if (!strncasecmp(cmdbuf, "SPEX", 4)) {
1289                 cmd_spex(&cmdbuf[5]);
1290         }
1291
1292         else if (!strncasecmp(cmdbuf, "CONF", 4)) {
1293                 cmd_conf(&cmdbuf[5]);
1294         }
1295
1296         else if (!strncasecmp(cmdbuf, "SEEN", 4)) {
1297                 cmd_seen(&cmdbuf[5]);
1298         }
1299
1300         else if (!strncasecmp(cmdbuf, "GTSN", 4)) {
1301                 cmd_gtsn(&cmdbuf[5]);
1302         }
1303
1304         else if (!strncasecmp(cmdbuf, "VIEW", 4)) {
1305                 cmd_view(&cmdbuf[5]);
1306         }
1307
1308         else if (!strncasecmp(cmdbuf, "ISME", 4)) {
1309                 cmd_isme(&cmdbuf[5]);
1310         }
1311
1312         else if (!DLoader_Exec_Cmd(cmdbuf)) {
1313                 cprintf("%d Unrecognized or unsupported command.\n",
1314                         ERROR + CMD_NOT_SUPPORTED);
1315                }
1316
1317         unbuffer_output();
1318
1319         /* Run any after-each-command routines registered by modules */
1320         PerformSessionHooks(EVT_CMD);
1321 }
1322
1323
1324 /*
1325  * This loop performs all asynchronous functions.
1326  */
1327 void do_async_loop(void) {
1328         PerformSessionHooks(EVT_ASYNC);
1329 }