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