citadel/citserver.c

   1 /*
   2  * $Id$
   3  *
   4  * Main source module for the Citadel server
   5  *
   6  */
   7
   8 #ifdef DLL_EXPORT
   9 #define IN_LIBCIT
  10 #endif
  11
  12 #include "sysdep.h"
  13 #include <stdlib.h>
  14 #include <unistd.h>
  15 #include <stdio.h>
  16 #include <fcntl.h>
  17 #include <signal.h>
  18 #include <sys/types.h>
  19 #include <sys/stat.h>
  20
  21
  22 #if TIME_WITH_SYS_TIME
  23 # include <sys/time.h>
  24 # include <time.h>
  25 #else
  26 # if HAVE_SYS_TIME_H
  27 #  include <sys/time.h>
  28 # else
  29 #  include <time.h>
  30 # endif
  31 #endif
  32
  33 #include <ctype.h>
  34 #include <string.h>
  35 #include <errno.h>
  36 #include <limits.h>
  37 /* #include <dlfcn.h> */
  38 #include <netdb.h>
  39 #include <sys/types.h>
  40 #include <sys/socket.h>
  41 #include <netinet/in.h>
  42 #include <arpa/inet.h>
  43 #include "citadel.h"
  44 #include "server.h"
  45 #include "serv_extensions.h"
  46 #include "sysdep_decls.h"
  47 #include "citserver.h"
  48 #include "config.h"
  49 #include "database.h"
  50 #include "housekeeping.h"
  51 #include "user_ops.h"
  52 #include "msgbase.h"
  53 #include "support.h"
  54 #include "locate_host.h"
  55 #include "room_ops.h"
  56 #include "file_ops.h"
  57 #include "policy.h"
  58 #include "control.h"
  59 #include "tools.h"
  60
  61 #ifndef HAVE_SNPRINTF
  62 #include "snprintf.h"
  63 #endif
  64
  65 struct CitContext *ContextList = NULL;
  66 struct CitContext* next_session = NULL;
  67 char *unique_session_numbers;
  68 int ScheduledShutdown = 0;
  69 int do_defrag = 0;
  70 time_t server_startup_time;
  71
  72 /*
  73  * Various things that need to be initialized at startup
  74  */
  75 void master_startup(void) {
  76         struct timeval tv;
  77         unsigned int seed;
  78         FILE *urandom;
  79         struct ctdlroom qrbuf;
  80
  81         lprintf(CTDL_DEBUG, "master_startup() started\n");
  82         time(&server_startup_time);
  83
  84         lprintf(CTDL_INFO, "Opening databases\n");
  85         open_databases();
  86
  87         if (do_defrag) {
  88                 defrag_databases();
  89         }
  90
  91         check_ref_counts();
  92
  93         lprintf(CTDL_INFO, "Creating base rooms (if necessary)\n");
  94         create_room(BASEROOM,           0, "", 0, 1, 0, VIEW_BBS);
  95         create_room(AIDEROOM,           3, "", 0, 1, 0, VIEW_BBS);
  96         create_room(SYSCONFIGROOM,      3, "", 0, 1, 0, VIEW_BBS);
  97         create_room(config.c_twitroom,  0, "", 0, 1, 0, VIEW_BBS);
  98
  99         /* The "Local System Configuration" room doesn't need to be visible */
 100         if (lgetroom(&qrbuf, SYSCONFIGROOM) == 0) {
 101                 qrbuf.QRflags2 |= QR2_SYSTEM;
 102                 lputroom(&qrbuf);
 103         }
 104
 105         lprintf(CTDL_INFO, "Seeding the pseudo-random number generator...\n");
 106         urandom = fopen("/dev/urandom", "r");
 107         if (urandom != NULL) {
 108                 fread(&seed, sizeof seed, 1, urandom);
 109                 fclose(urandom);
 110         }
 111         else {
 112                 gettimeofday(&tv, NULL);
 113                 seed = tv.tv_usec;
 114         }
 115         srandom(seed);
 116
 117         lprintf(CTDL_INFO, "Initializing ipgm secret\n");
 118         get_config();
 119         config.c_ipgm_secret = rand();
 120         put_config();
 121
 122         lprintf(CTDL_DEBUG, "master_startup() finished\n");
 123 }
 124
 125
 126 /*
 127  * Cleanup routine to be called when the server is shutting down.
 128  * WARNING: It's no longer safe to call this function to force a shutdown.
 129  * Instead, set time_to_die = 1.
 130  */
 131 void master_cleanup(void) {
 132         struct CleanupFunctionHook *fcn;
 133
 134         /* Run any cleanup routines registered by loadable modules */
 135         for (fcn = CleanupHookTable; fcn != NULL; fcn = fcn->next) {
 136                 (*fcn->h_function_pointer)();
 137         }
 138
 139         /* Close databases */
 140         lprintf(CTDL_INFO, "Closing databases\n");
 141         close_databases();
 142
 143         /* Do system-dependent stuff */
 144         sysdep_master_cleanup();
 145
 146 #ifdef DEBUG_MEMORY_LEAKS
 147         dump_heap();
 148 #endif
 149
 150         /* Now go away. */
 151         lprintf(CTDL_NOTICE, "citserver: exiting.\n");
 152         fflush(stdout); fflush(stderr);
 153         exit(0);
 154 }
 155
 156
 157 /*
 158  * Free any per-session data allocated by modules or whatever
 159  */
 160 void deallocate_user_data(struct CitContext *con)
 161 {
 162         struct CtdlSessData *ptr;
 163
 164         begin_critical_section(S_SESSION_TABLE);
 165         while (con->FirstSessData != NULL) {
 166                 lprintf(CTDL_DEBUG, "Deallocating user data symbol %ld\n",
 167                         con->FirstSessData->sym_id);
 168                 if (con->FirstSessData->sym_data != NULL)
 169                         free(con->FirstSessData->sym_data);
 170                 ptr = con->FirstSessData->next;
 171                 free(con->FirstSessData);
 172                 con->FirstSessData = ptr;
 173         }
 174         end_critical_section(S_SESSION_TABLE);
 175 }
 176
 177
 178
 179
 180 /*
 181  * Terminate a session and remove its context data structure.
 182  */
 183 void RemoveContext (struct CitContext *con)
 184 {
 185         struct CitContext *ptr = NULL;
 186         struct CitContext *ToFree = NULL;
 187
 188         if (con==NULL) {
 189                 lprintf(CTDL_ERR, "WARNING: RemoveContext() called with NULL!\n");
 190                 return;
 191         }
 192         lprintf(CTDL_DEBUG, "RemoveContext() called\n");
 193
 194         /* Remove the context from the global context list.  This needs
 195          * to get done FIRST to avoid concurrency problems.  It is *vitally*
 196          * important to keep num_sessions accurate!!
 197          */
 198         lprintf(CTDL_DEBUG, "Removing context for session %d\n", con->cs_pid);
 199         begin_critical_section(S_SESSION_TABLE);
 200         if (ContextList == con) {
 201                 ToFree = ContextList;
 202                 ContextList = ContextList->next;
 203                 --num_sessions;
 204         }
 205         else {
 206                 for (ptr = ContextList; ptr != NULL; ptr = ptr->next) {
 207                         if (ptr->next == con) {
 208                                 /* See fair scheduling in sysdep.c */
 209                                 if (next_session == ptr->next)
 210                                         next_session = ptr->next->next;
 211                                 ToFree = ptr->next;
 212                                 ptr->next = ptr->next->next;
 213                                 --num_sessions;
 214                         }
 215                 }
 216         }
 217         end_critical_section(S_SESSION_TABLE);
 218
 219         if (ToFree == NULL) {
 220                 lprintf(CTDL_DEBUG, "RemoveContext() found nothing to remove\n");
 221                 return;
 222         }
 223
 224         /* Run any cleanup routines registered by loadable modules.
 225          * Note 1: This must occur *before* deallocate_user_data() because the
 226          *         cleanup functions might touch dynamic session data.
 227          * Note 2: We have to "become_session()" because the cleanup functions
 228          *         might make references to "CC" assuming it's the right one.
 229          */
 230         become_session(con);
 231         PerformSessionHooks(EVT_STOP);
 232         become_session(NULL);
 233
 234         /* Now handle all of the administrivia. */
 235         lprintf(CTDL_DEBUG, "Calling logout(%d)\n", con->cs_pid);
 236         logout(con);
 237
 238         unlink(con->temp);
 239         lprintf(CTDL_NOTICE, "[%3d] Session ended.\n", con->cs_pid);
 240
 241         /* Deallocate any user-data attached to this session */
 242         deallocate_user_data(con);
 243
 244         /* If the client is still connected, blow 'em away. */
 245         lprintf(CTDL_DEBUG, "Closing socket %d\n", con->client_socket);
 246         close(con->client_socket);
 247
 248         /* This is where we used to check for scheduled shutdowns. */
 249
 250         /* Free up the memory used by this context */
 251         free(con);
 252
 253         lprintf(CTDL_DEBUG, "Done with RemoveContext()\n");
 254 }
 255
 256
 257
 258
 259
 260 /*
 261  * Return a pointer to some generic per-session user data.
 262  * (This function returns NULL if the requested symbol is not allocated.)
 263  *
 264  * NOTE: we use critical sections for allocating and de-allocating these,
 265  *       but not for locating one.
 266  */
 267 void *CtdlGetUserData(unsigned long requested_sym)
 268 {
 269         struct CtdlSessData *ptr;
 270
 271         for (ptr = CC->FirstSessData; ptr != NULL; ptr = ptr->next)
 272                 if (ptr->sym_id == requested_sym)
 273                         return(ptr->sym_data);
 274
 275         lprintf(CTDL_ERR, "ERROR! CtdlGetUserData(%ld) symbol not allocated\n",
 276                 requested_sym);
 277         return NULL;
 278 }
 279
 280
 281 /*
 282  * Allocate some generic per-session user data.
 283  */
 284 void CtdlAllocUserData(unsigned long requested_sym, size_t num_bytes)
 285 {
 286         struct CtdlSessData *ptr;
 287
 288         lprintf(CTDL_DEBUG, "CtdlAllocUserData(%ld) called\n", requested_sym);
 289
 290         /* Fail silently if the symbol is already registered. */
 291         for (ptr = CC->FirstSessData; ptr != NULL; ptr = ptr->next)  {
 292                 if (ptr->sym_id == requested_sym) {
 293                         return;
 294                 }
 295         }
 296
 297         /* Grab us some memory!  Dem's good eatin' !!  */
 298         ptr = malloc(sizeof(struct CtdlSessData));
 299         ptr->sym_id = requested_sym;
 300         ptr->sym_data = malloc(num_bytes);
 301         memset(ptr->sym_data, 0, num_bytes);
 302
 303         begin_critical_section(S_SESSION_TABLE);
 304         ptr->next = CC->FirstSessData;
 305         CC->FirstSessData = ptr;
 306         end_critical_section(S_SESSION_TABLE);
 307
 308         lprintf(CTDL_DEBUG, "CtdlAllocUserData(%ld) finished\n", requested_sym);
 309 }
 310
 311
 312 /*
 313  * Change the size of a buffer allocated with CtdlAllocUserData()
 314  */
 315 void CtdlReallocUserData(unsigned long requested_sym, size_t num_bytes)
 316 {
 317         struct CtdlSessData *ptr;
 318
 319         for (ptr = CC->FirstSessData; ptr != NULL; ptr = ptr->next)  {
 320                 if (ptr->sym_id == requested_sym) {
 321                         ptr->sym_data = realloc(ptr->sym_data, num_bytes);
 322                         return;
 323                 }
 324         }
 325
 326         lprintf(CTDL_ERR, "CtdlReallocUserData() ERROR: symbol %ld not found!\n",
 327                 requested_sym);
 328 }
 329
 330
 331
 332
 333
 334
 335 /*
 336  * cmd_info()  -  tell the client about this server
 337  */
 338 void cmd_info(void) {
 339         cprintf("%d Server info:\n", LISTING_FOLLOWS);
 340         cprintf("%d\n", CC->cs_pid);
 341         cprintf("%s\n", config.c_nodename);
 342         cprintf("%s\n", config.c_humannode);
 343         cprintf("%s\n", config.c_fqdn);
 344         cprintf("%s\n", CITADEL);
 345         cprintf("%d\n", REV_LEVEL);
 346         cprintf("%s\n", config.c_bbs_city);
 347         cprintf("%s\n", config.c_sysadm);
 348         cprintf("%d\n", SERVER_TYPE);
 349         cprintf("%s\n", config.c_moreprompt);
 350         cprintf("1\n"); /* 1 = yes, this system supports floors */
 351         cprintf("1\n"); /* 1 = we support the extended paging options */
 352         cprintf("%s\n", CC->cs_nonce);
 353         cprintf("1\n"); /* 1 = yes, this system supports the QNOP command */
 354 #ifdef HAVE_LDAP
 355         cprintf("1\n"); /* 1 = yes, this server is LDAP-enabled */
 356 #else
 357         cprintf("0\n"); /* 1 = no, this server is not LDAP-enabled */
 358 #endif
 359         cprintf("000\n");
 360 }
 361
 362
 363 /*
 364  * returns an asterisk if there are any instant messages waiting,
 365  * space otherwise.
 366  */
 367 char CtdlCheckExpress(void) {
 368         if (CC->FirstExpressMessage == NULL) {
 369                 return(' ');
 370         }
 371         else {
 372                 return('*');
 373         }
 374 }
 375
 376 void cmd_time(void)
 377 {
 378    time_t tv;
 379    struct tm tmp;
 380
 381    tv = time(NULL);
 382    localtime_r(&tv, &tmp);
 383
 384    /* timezone and daylight global variables are not portable. */
 385 #ifdef HAVE_STRUCT_TM_TM_GMTOFF
 386    cprintf("%d %ld|%ld|%d\n", CIT_OK, (long)tv, tmp.tm_gmtoff, tmp.tm_isdst);
 387 #else
 388    cprintf("%d %ld|%ld|%d\n", CIT_OK, (long)tv, timezone, tmp.tm_isdst);
 389 #endif
 390 }
 391
 392
 393 /*
 394  * Check originating host against the public_clients file.  This determines
 395  * whether the client is allowed to change the hostname for this session
 396  * (for example, to show the location of the user rather than the location
 397  * of the client).
 398  */
 399 int is_public_client(void)
 400 {
 401         char buf[SIZ];
 402         char addrbuf[SIZ];
 403         FILE *fp;
 404         int i;
 405         struct stat statbuf;
 406         static time_t pc_timestamp = 0;
 407         static char public_clients[SIZ];
 408
 409 #define PUBLIC_CLIENTS "./public_clients"
 410
 411         /*
 412          * Check the time stamp on the public_clients file.  If it's been
 413          * updated since the last time we were here (or if this is the first
 414          * time we've been through the loop), read its contents and learn
 415          * the IP addresses of the listed hosts.
 416          */
 417         if (stat(PUBLIC_CLIENTS, &statbuf) != 0) {
 418                 /* No public_clients file exists, so bail out */
 419                 lprintf(CTDL_WARNING, "Warning: '%s' does not exist\n", PUBLIC_CLIENTS);
 420                 return(0);
 421         }
 422
 423         if (statbuf.st_mtime > pc_timestamp) {
 424                 begin_critical_section(S_PUBLIC_CLIENTS);
 425                 lprintf(CTDL_INFO, "Loading %s\n", PUBLIC_CLIENTS);
 426
 427                 strcpy(public_clients, "127.0.0.1");
 428                 if (hostname_to_dotted_quad(addrbuf, config.c_fqdn) == 0) {
 429                         strcat(public_clients, "|");
 430                         strcat(public_clients, addrbuf);
 431                 }
 432
 433                 fp = fopen("public_clients", "r");
 434                 if (fp != NULL) while (fgets(buf, sizeof buf, fp)!=NULL) {
 435                         for (i=0; i<strlen(buf); ++i) {
 436                                 if (buf[i] == '#') buf[i] = 0;
 437                         }
 438                         while (isspace((buf[strlen(buf)-1]))) {
 439                                 buf[strlen(buf)-1] = 0;
 440                         }
 441                         if (hostname_to_dotted_quad(addrbuf, buf) == 0) {
 442                                 if ((strlen(public_clients) +
 443                                    strlen(addrbuf) + 2)
 444                                    < sizeof(public_clients)) {
 445                                         strcat(public_clients, addrbuf);
 446                                 }
 447                         }
 448                 }
 449                 fclose(fp);
 450                 pc_timestamp = time(NULL);
 451                 end_critical_section(S_PUBLIC_CLIENTS);
 452         }
 453
 454         lprintf(CTDL_DEBUG, "Checking whether %s is a local or public client\n",
 455                 CC->cs_addr);
 456         for (i=0; i<num_parms(public_clients); ++i) {
 457                 extract(addrbuf, public_clients, i);
 458                 if (!strcasecmp(CC->cs_addr, addrbuf)) {
 459                         lprintf(CTDL_DEBUG, "... yes it is.\n");
 460                         return(1);
 461                 }
 462         }
 463
 464         /* No hits.  This is not a public client. */
 465         lprintf(CTDL_DEBUG, "... no it isn't.\n");
 466         return(0);
 467 }
 468
 469
 470 /*
 471  * the client is identifying itself to the server
 472  */
 473 void cmd_iden(char *argbuf)
 474 {
 475         int dev_code;
 476         int cli_code;
 477         int rev_level;
 478         char desc[SIZ];
 479         char from_host[SIZ];
 480         struct in_addr addr;
 481         int do_lookup = 0;
 482
 483         if (num_parms(argbuf)<4) {
 484                 cprintf("%d usage error\n", ERROR + ILLEGAL_VALUE);
 485                 return;
 486         }
 487
 488         dev_code = extract_int(argbuf,0);
 489         cli_code = extract_int(argbuf,1);
 490         rev_level = extract_int(argbuf,2);
 491         extract(desc,argbuf,3);
 492
 493         safestrncpy(from_host, config.c_fqdn, sizeof from_host);
 494         from_host[sizeof from_host - 1] = 0;
 495         if (num_parms(argbuf)>=5) extract(from_host,argbuf,4);
 496
 497         CC->cs_clientdev = dev_code;
 498         CC->cs_clienttyp = cli_code;
 499         CC->cs_clientver = rev_level;
 500         safestrncpy(CC->cs_clientname, desc, sizeof CC->cs_clientname);
 501         CC->cs_clientname[31] = 0;
 502
 503         if (strlen(from_host) > 0) {
 504                 if (CC->is_local_socket) do_lookup = 1;
 505                 else if (is_public_client()) do_lookup = 1;
 506         }
 507
 508         if (do_lookup) {
 509                 lprintf(CTDL_DEBUG, "Looking up hostname '%s'\n", from_host);
 510                 if ((addr.s_addr = inet_addr(from_host)) != -1) {
 511                         locate_host(CC->cs_host, sizeof CC->cs_host,
 512                                 NULL, 0,
 513                                 &addr);
 514                 }
 515                 else {
 516                         safestrncpy(CC->cs_host, from_host, sizeof CC->cs_host);
 517                         CC->cs_host[sizeof CC->cs_host - 1] = 0;
 518                 }
 519         }
 520
 521         lprintf(CTDL_NOTICE, "Client %d/%d/%01d.%02d (%s) from %s\n",
 522                 dev_code,
 523                 cli_code,
 524                 (rev_level / 100),
 525                 (rev_level % 100),
 526                 desc,
 527                 CC->cs_host);
 528         cprintf("%d Ok\n",CIT_OK);
 529 }
 530
 531
 532 /*
 533  * display system messages or help
 534  */
 535 void cmd_mesg(char *mname)
 536 {
 537         FILE *mfp;
 538         char targ[SIZ];
 539         char buf[SIZ];
 540         char buf2[SIZ];
 541         char *dirs[2];
 542
 543         extract(buf,mname,0);
 544
 545         dirs[0]=malloc(64);
 546         dirs[1]=malloc(64);
 547         strcpy(dirs[0],"messages");
 548         strcpy(dirs[1],"help");
 549         snprintf(buf2, sizeof buf2, "%s.%d.%d", buf, CC->cs_clientdev, CC->cs_clienttyp);
 550         mesg_locate(targ,sizeof targ,buf2,2,(const char **)dirs);
 551         if (strlen(targ) == 0) {
 552                 snprintf(buf2, sizeof buf2, "%s.%d", buf, CC->cs_clientdev);
 553                 mesg_locate(targ,sizeof targ,buf2,2,(const char **)dirs);
 554                 if (strlen(targ) == 0) {
 555                         mesg_locate(targ,sizeof targ,buf,2,(const char **)dirs);
 556                 }
 557         }
 558         free(dirs[0]);
 559         free(dirs[1]);
 560
 561         if (strlen(targ)==0) {
 562                 cprintf("%d '%s' not found.\n",ERROR + FILE_NOT_FOUND, mname);
 563                 return;
 564         }
 565
 566         mfp = fopen(targ,"r");
 567         if (mfp==NULL) {
 568                 cprintf("%d Cannot open '%s': %s\n",
 569                         ERROR + INTERNAL_ERROR, targ, strerror(errno));
 570                 return;
 571         }
 572         cprintf("%d %s\n",LISTING_FOLLOWS,buf);
 573
 574         while (fgets(buf, (SIZ-1), mfp)!=NULL) {
 575                 buf[strlen(buf)-1] = 0;
 576                 do_help_subst(buf);
 577                 cprintf("%s\n",buf);
 578         }
 579
 580         fclose(mfp);
 581         cprintf("000\n");
 582 }
 583
 584
 585 /*
 586  * enter system messages or help
 587  */
 588 void cmd_emsg(char *mname)
 589 {
 590         FILE *mfp;
 591         char targ[SIZ];
 592         char buf[SIZ];
 593         char *dirs[2];
 594         int a;
 595
 596         unbuffer_output();
 597
 598         if (CtdlAccessCheck(ac_aide)) return;
 599
 600         extract(buf,mname,0);
 601         for (a=0; a<strlen(buf); ++a) {         /* security measure */
 602                 if (buf[a] == '/') buf[a] = '.';
 603         }
 604
 605         dirs[0]=malloc(64);
 606         dirs[1]=malloc(64);
 607         strcpy(dirs[0],"messages");
 608         strcpy(dirs[1],"help");
 609         mesg_locate(targ,sizeof targ,buf,2,(const char**)dirs);
 610         free(dirs[0]);
 611         free(dirs[1]);
 612
 613         if (strlen(targ)==0) {
 614                 snprintf(targ, sizeof targ, "./help/%s", buf);
 615         }
 616
 617         mfp = fopen(targ,"w");
 618         if (mfp==NULL) {
 619                 cprintf("%d Cannot open '%s': %s\n",
 620                         ERROR + INTERNAL_ERROR, targ, strerror(errno));
 621                 return;
 622         }
 623         cprintf("%d %s\n", SEND_LISTING, targ);
 624
 625         while (client_gets(buf), strcmp(buf, "000")) {
 626                 fprintf(mfp, "%s\n", buf);
 627         }
 628
 629         fclose(mfp);
 630 }
 631
 632
 633 /* Don't show the names of private rooms unless the viewing
 634  * user also knows the rooms.
 635  */
 636 void GenerateRoomDisplay(char *real_room,
 637                         struct CitContext *viewed,
 638                         struct CitContext *viewer) {
 639
 640         strcpy(real_room, viewed->room.QRname);
 641         if (viewed->room.QRflags & QR_MAILBOX) {
 642                 strcpy(real_room, &real_room[11]);
 643         }
 644         if (viewed->room.QRflags & QR_PRIVATE) {
 645                 if ( (CtdlRoomAccess(&viewed->room, &viewer->user)
 646                    & UA_KNOWN) == 0) {
 647                         strcpy(real_room, "<private room>");
 648                 }
 649         }
 650
 651         if (viewed->cs_flags & CS_CHAT) {
 652                 while (strlen(real_room) < 14)
 653                         strcat(real_room, " ");
 654
 655                 strcpy(&real_room[14], "<chat>");
 656         }
 657
 658 }
 659
 660 /*
 661  * Convenience function.
 662  */
 663 int CtdlAccessCheck(int required_level) {
 664
 665         if (CC->internal_pgm) return(0);
 666         if (required_level >= ac_internal) {
 667                 cprintf("%d This is not a user-level command.\n",
 668                         ERROR + HIGHER_ACCESS_REQUIRED);
 669                 return(-1);
 670         }
 671
 672         if (CC->user.axlevel >= 6) return(0);
 673         if (required_level >= ac_aide) {
 674                 cprintf("%d This command requires Aide access.\n",
 675                         ERROR + HIGHER_ACCESS_REQUIRED);
 676                 return(-1);
 677         }
 678
 679         if (is_room_aide()) return(0);
 680         if (required_level >= ac_room_aide) {
 681                 cprintf("%d This command requires Aide or Room Aide access.\n",
 682                         ERROR + HIGHER_ACCESS_REQUIRED);
 683                 return(-1);
 684         }
 685
 686         if (CC->logged_in) return(0);
 687         if (required_level >= ac_logged_in) {
 688                 cprintf("%d Not logged in.\n", ERROR + NOT_LOGGED_IN);
 689                 return(-1);
 690         }
 691
 692         /* shhh ... succeed quietly */
 693         return(0);
 694 }
 695
 696
 697
 698 /*
 699  * Terminate another running session
 700  */
 701 void cmd_term(char *cmdbuf)
 702 {
 703         int session_num;
 704         struct CitContext *ccptr;
 705         int found_it = 0;
 706         int allowed = 0;
 707
 708         session_num = extract_int(cmdbuf, 0);
 709         if (session_num == CC->cs_pid) {
 710                 cprintf("%d You can't kill your own session.\n", ERROR + ILLEGAL_VALUE);
 711                 return;
 712         }
 713
 714         lprintf(CTDL_DEBUG, "Locating session to kill\n");
 715         begin_critical_section(S_SESSION_TABLE);
 716         for (ccptr = ContextList; ccptr != NULL; ccptr = ccptr->next) {
 717                 if (session_num == ccptr->cs_pid) {
 718                         found_it = 1;
 719                         if ((ccptr->user.usernum == CC->user.usernum)
 720                            || (CC->user.axlevel >= 6)) {
 721                                 allowed = 1;
 722                                 ccptr->kill_me = 1;
 723                         }
 724                         else {
 725                                 allowed = 0;
 726                         }
 727                 }
 728         }
 729         end_critical_section(S_SESSION_TABLE);
 730
 731         if (found_it) {
 732                 if (allowed) {
 733                         cprintf("%d Session terminated.\n", CIT_OK);
 734                 }
 735                 else {
 736                         cprintf("%d You are not allowed to do that.\n",
 737                                 ERROR + HIGHER_ACCESS_REQUIRED);
 738                 }
 739         }
 740         else {
 741                 cprintf("%d No such session.\n", ERROR + ILLEGAL_VALUE);
 742         }
 743 }
 744
 745
 746
 747
 748
 749 /*
 750  * get the paginator prompt
 751  */
 752 void cmd_more(void) {
 753         cprintf("%d %s\n", CIT_OK, config.c_moreprompt);
 754 }
 755
 756 /*
 757  * echo
 758  */
 759 void cmd_echo(char *etext)
 760 {
 761         cprintf("%d %s\n", CIT_OK, etext);
 762 }
 763
 764
 765
 766 /*
 767  * identify as internal program
 768  */
 769 void cmd_ipgm(char *argbuf)
 770 {
 771         int secret;
 772
 773         secret = extract_int(argbuf, 0);
 774
 775         /* For security reasons, we do NOT allow this command to run
 776          * over the network.  Local sockets only.
 777          */
 778         if (!CC->is_local_socket) {
 779                 sleep(5);
 780                 cprintf("%d Authentication failed.\n", ERROR + PASSWORD_REQUIRED);
 781         }
 782         else if (secret == config.c_ipgm_secret) {
 783                 CC->internal_pgm = 1;
 784                 strcpy(CC->curr_user, "<internal program>");
 785                 CC->cs_flags = CC->cs_flags|CS_STEALTH;
 786                 cprintf("%d Authenticated as an internal program.\n", CIT_OK);
 787         }
 788         else {
 789                 sleep(5);
 790                 cprintf("%d Authentication failed.\n", ERROR + PASSWORD_REQUIRED);
 791                 lprintf(CTDL_ERR, "Warning: ipgm authentication failed.\n");
 792                 CC->kill_me = 1;
 793         }
 794
 795         /* Now change the ipgm secret for the next round. */
 796         get_config();
 797         config.c_ipgm_secret = rand();
 798         put_config();
 799 }
 800
 801
 802 /*
 803  * Shut down the server
 804  */
 805 void cmd_down(void) {
 806
 807         if (CtdlAccessCheck(ac_aide)) return;
 808
 809         cprintf("%d Shutting down server.  Goodbye.\n", CIT_OK);
 810         time_to_die = 1;
 811 }
 812
 813 /*
 814  * Schedule or cancel a server shutdown
 815  */
 816 void cmd_scdn(char *argbuf)
 817 {
 818         int new_state;
 819
 820         if (CtdlAccessCheck(ac_aide)) return;
 821
 822         new_state = extract_int(argbuf, 0);
 823         if ((new_state == 0) || (new_state == 1)) {
 824                 ScheduledShutdown = new_state;
 825         }
 826         cprintf("%d %d\n", CIT_OK, ScheduledShutdown);
 827 }
 828
 829
 830 /*
 831  * Set or unset asynchronous protocol mode
 832  */
 833 void cmd_asyn(char *argbuf)
 834 {
 835         int new_state;
 836
 837         new_state = extract_int(argbuf, 0);
 838         if ((new_state == 0) || (new_state == 1)) {
 839                 CC->is_async = new_state;
 840         }
 841         cprintf("%d %d\n", CIT_OK, CC->is_async);
 842 }
 843
 844
 845 /*
 846  * Generate a "nonce" for APOP-style authentication.
 847  *
 848  * RFC 1725 et al specify a PID to be placed in front of the nonce.
 849  * Quoth BTX: That would be stupid.
 850  */
 851 void generate_nonce(struct CitContext *con) {
 852         struct timeval tv;
 853
 854         memset(con->cs_nonce, NONCE_SIZE, 0);
 855         gettimeofday(&tv, NULL);
 856         memset(con->cs_nonce, NONCE_SIZE, 0);
 857         snprintf(con->cs_nonce, NONCE_SIZE, "<%d%ld@%s>",
 858                 rand(), (long)tv.tv_usec, config.c_fqdn);
 859 }
 860
 861
 862
 863
 864 /*
 865  * Back-end function for starting a session
 866  */
 867 void begin_session(struct CitContext *con)
 868 {
 869         int len;        /* should be socklen_t but doesn't work on Macintosh */
 870         struct sockaddr_in sin;
 871
 872         /*
 873          * Initialize some variables specific to our context.
 874          */
 875         con->logged_in = 0;
 876         con->internal_pgm = 0;
 877         con->download_fp = NULL;
 878         con->upload_fp = NULL;
 879         con->FirstExpressMessage = NULL;
 880         time(&con->lastcmd);
 881         time(&con->lastidle);
 882         strcpy(con->lastcmdname, "    ");
 883         strcpy(con->cs_clientname, "(unknown)");
 884         strcpy(con->curr_user, NLI);
 885         strcpy(con->net_node,"");
 886         strcpy(con->fake_username, "");
 887         strcpy(con->fake_postname, "");
 888         strcpy(con->fake_hostname, "");
 889         strcpy(con->fake_roomname, "");
 890         generate_nonce(con);
 891         snprintf(con->temp, sizeof con->temp, tmpnam(NULL));
 892         safestrncpy(con->cs_host, config.c_fqdn, sizeof con->cs_host);
 893         safestrncpy(con->cs_addr, "", sizeof con->cs_addr);
 894         con->cs_host[sizeof con->cs_host - 1] = 0;
 895         len = sizeof sin;
 896         if (!CC->is_local_socket) {
 897                 if (!getpeername(con->client_socket,
 898                    (struct sockaddr *) &sin, &len))
 899                         locate_host(con->cs_host, sizeof con->cs_host,
 900                                 con->cs_addr, sizeof con->cs_addr,
 901                                 &sin.sin_addr);
 902         }
 903         else {
 904                 strcpy(con->cs_host, "");
 905         }
 906         con->cs_flags = 0;
 907         con->upload_type = UPL_FILE;
 908         con->dl_is_net = 0;
 909         con->FirstSessData = NULL;
 910
 911         con->nologin = 0;
 912         if ((config.c_maxsessions > 0)&&(num_sessions > config.c_maxsessions))
 913                 con->nologin = 1;
 914
 915         lprintf(CTDL_NOTICE, "Session started.\n");
 916
 917         /* Run any session startup routines registered by loadable modules */
 918         PerformSessionHooks(EVT_START);
 919 }
 920
 921
 922 void citproto_begin_session() {
 923         if (CC->nologin==1) {
 924                 cprintf("%d %s: Too many users are already online "
 925                         "(maximum is %d)\n",
 926                         ERROR + MAX_SESSIONS_EXCEEDED,
 927                         config.c_nodename, config.c_maxsessions);
 928         }
 929         else {
 930                 cprintf("%d %s Citadel server ready.\n",
 931                         CIT_OK, config.c_nodename);
 932         }
 933 }
 934
 935
 936
 937
 938 /*
 939  * This loop recognizes all server commands.
 940  */
 941 void do_command_loop(void) {
 942         char cmdbuf[SIZ];
 943
 944         time(&CC->lastcmd);
 945         memset(cmdbuf, 0, sizeof cmdbuf); /* Clear it, just in case */
 946         if (client_gets(cmdbuf) < 1) {
 947                 lprintf(CTDL_ERR, "Client socket is broken; ending session\n");
 948                 CC->kill_me = 1;
 949                 return;
 950         }
 951         lprintf(CTDL_INFO, "Citadel: %s\n", cmdbuf);
 952
 953         buffer_output();
 954
 955         /*
 956          * Let other clients see the last command we executed, and
 957          * update the idle time, but not NOOP, QNOP, PEXP, or GEXP.
 958          */
 959         if ( (strncasecmp(cmdbuf, "NOOP", 4))
 960            && (strncasecmp(cmdbuf, "QNOP", 4))
 961            && (strncasecmp(cmdbuf, "PEXP", 4))
 962            && (strncasecmp(cmdbuf, "GEXP", 4)) ) {
 963                 strcpy(CC->lastcmdname, "    ");
 964                 safestrncpy(CC->lastcmdname, cmdbuf,
 965                         sizeof(CC->lastcmdname) );
 966                 time(&CC->lastidle);
 967         }
 968
 969         if ((strncasecmp(cmdbuf, "ENT0", 4))
 970            && (strncasecmp(cmdbuf, "MESG", 4))
 971            && (strncasecmp(cmdbuf, "MSGS", 4)))
 972         {
 973            CC->cs_flags &= ~CS_POSTING;
 974         }
 975
 976         if (!strncasecmp(cmdbuf,"NOOP",4)) {
 977                 cprintf("%d%cok\n", CIT_OK, CtdlCheckExpress() );
 978         }
 979
 980         else if (!strncasecmp(cmdbuf,"QNOP",4)) {
 981                 /* do nothing, this command returns no response */
 982         }
 983
 984         else if (!strncasecmp(cmdbuf,"QUIT",4)) {
 985                 cprintf("%d Goodbye.\n", CIT_OK);
 986                 CC->kill_me = 1;
 987         }
 988
 989         else if (!strncasecmp(cmdbuf,"ASYN",4)) {
 990                 cmd_asyn(&cmdbuf[5]);
 991         }
 992
 993         else if (!strncasecmp(cmdbuf,"LOUT",4)) {
 994                 if (CC->logged_in) logout(CC);
 995                 cprintf("%d logged out.\n", CIT_OK);
 996         }
 997
 998         else if (!strncasecmp(cmdbuf,"USER",4)) {
 999                 cmd_user(&cmdbuf[5]);
1000         }
1001
1002         else if (!strncasecmp(cmdbuf,"PASS",4)) {
1003                 cmd_pass(&cmdbuf[5]);
1004         }
1005
1006         else if (!strncasecmp(cmdbuf,"NEWU",4)) {
1007                 cmd_newu(&cmdbuf[5]);
1008         }
1009
1010         else if (!strncasecmp(cmdbuf,"CREU",4)) {
1011                 cmd_creu(&cmdbuf[5]);
1012         }
1013
1014         else if (!strncasecmp(cmdbuf,"SETP",4)) {
1015                 cmd_setp(&cmdbuf[5]);
1016         }
1017
1018         else if (!strncasecmp(cmdbuf,"LRMS",4)) {
1019                 cmd_lrms(&cmdbuf[5]);
1020         }
1021
1022         else if (!strncasecmp(cmdbuf,"LKRA",4)) {
1023                 cmd_lkra(&cmdbuf[5]);
1024         }
1025
1026         else if (!strncasecmp(cmdbuf,"LKRN",4)) {
1027                 cmd_lkrn(&cmdbuf[5]);
1028         }
1029
1030         else if (!strncasecmp(cmdbuf,"LKRO",4)) {
1031                 cmd_lkro(&cmdbuf[5]);
1032         }
1033
1034         else if (!strncasecmp(cmdbuf,"LZRM",4)) {
1035                 cmd_lzrm(&cmdbuf[5]);
1036         }
1037
1038         else if (!strncasecmp(cmdbuf,"LPRM",4)) {
1039                 cmd_lprm(&cmdbuf[5]);
1040         }
1041
1042         else if (!strncasecmp(cmdbuf,"GETU",4)) {
1043                 cmd_getu();
1044         }
1045
1046         else if (!strncasecmp(cmdbuf,"SETU",4)) {
1047                 cmd_setu(&cmdbuf[5]);
1048         }
1049
1050         else if (!strncasecmp(cmdbuf,"GOTO",4)) {
1051                 cmd_goto(&cmdbuf[5]);
1052         }
1053
1054         else if (!strncasecmp(cmdbuf,"MSGS",4)) {
1055                 cmd_msgs(&cmdbuf[5]);
1056         }
1057
1058         else if (!strncasecmp(cmdbuf,"WHOK",4)) {
1059                 cmd_whok();
1060         }
1061
1062         else if (!strncasecmp(cmdbuf,"RDIR",4)) {
1063                 cmd_rdir();
1064         }
1065
1066         else if (!strncasecmp(cmdbuf,"MSG0",4)) {
1067                 cmd_msg0(&cmdbuf[5]);
1068         }
1069
1070         else if (!strncasecmp(cmdbuf,"MSG2",4)) {
1071                 cmd_msg2(&cmdbuf[5]);
1072         }
1073
1074         else if (!strncasecmp(cmdbuf,"MSG3",4)) {
1075                 cmd_msg3(&cmdbuf[5]);
1076         }
1077
1078         else if (!strncasecmp(cmdbuf,"MSG4",4)) {
1079                 cmd_msg4(&cmdbuf[5]);
1080         }
1081
1082         else if (!strncasecmp(cmdbuf,"MSGP",4)) {
1083                 cmd_msgp(&cmdbuf[5]);
1084         }
1085
1086         else if (!strncasecmp(cmdbuf,"OPNA",4)) {
1087                 cmd_opna(&cmdbuf[5]);
1088         }
1089
1090         else if (!strncasecmp(cmdbuf,"INFO",4)) {
1091                 cmd_info();
1092         }
1093
1094         else if (!strncasecmp(cmdbuf,"SLRP",4)) {
1095                 cmd_slrp(&cmdbuf[5]);
1096         }
1097
1098         else if (!strncasecmp(cmdbuf,"INVT",4)) {
1099                 cmd_invt_kick(&cmdbuf[5],1);
1100         }
1101
1102         else if (!strncasecmp(cmdbuf,"KICK",4)) {
1103                 cmd_invt_kick(&cmdbuf[5],0);
1104         }
1105
1106         else if (!strncasecmp(cmdbuf,"GETR",4)) {
1107                 cmd_getr();
1108         }
1109
1110         else if (!strncasecmp(cmdbuf,"SETR",4)) {
1111                 cmd_setr(&cmdbuf[5]);
1112         }
1113
1114         else if (!strncasecmp(cmdbuf,"GETA",4)) {
1115                 cmd_geta();
1116         }
1117
1118         else if (!strncasecmp(cmdbuf,"SETA",4)) {
1119                 cmd_seta(&cmdbuf[5]);
1120         }
1121
1122         else if (!strncasecmp(cmdbuf,"ENT0",4)) {
1123                 cmd_ent0(&cmdbuf[5]);
1124         }
1125
1126         else if (!strncasecmp(cmdbuf,"RINF",4)) {
1127                 cmd_rinf();
1128         }
1129
1130         else if (!strncasecmp(cmdbuf,"DELE",4)) {
1131                 cmd_dele(&cmdbuf[5]);
1132         }
1133
1134         else if (!strncasecmp(cmdbuf,"KILL",4)) {
1135                 cmd_kill(&cmdbuf[5]);
1136         }
1137
1138         else if (!strncasecmp(cmdbuf,"CRE8",4)) {
1139                 cmd_cre8(&cmdbuf[5]);
1140         }
1141
1142         else if (!strncasecmp(cmdbuf,"MOVE",4)) {
1143                 cmd_move(&cmdbuf[5]);
1144         }
1145
1146         else if (!strncasecmp(cmdbuf,"FORG",4)) {
1147                 cmd_forg();
1148         }
1149
1150         else if (!strncasecmp(cmdbuf,"MESG",4)) {
1151                 cmd_mesg(&cmdbuf[5]);
1152         }
1153
1154         else if (!strncasecmp(cmdbuf,"EMSG",4)) {
1155                 cmd_emsg(&cmdbuf[5]);
1156         }
1157
1158         else if (!strncasecmp(cmdbuf,"GNUR",4)) {
1159                 cmd_gnur();
1160         }
1161
1162         else if (!strncasecmp(cmdbuf,"VALI",4)) {
1163                 cmd_vali(&cmdbuf[5]);
1164         }
1165
1166         else if (!strncasecmp(cmdbuf,"EINF",4)) {
1167                 cmd_einf(&cmdbuf[5]);
1168         }
1169
1170         else if (!strncasecmp(cmdbuf,"LIST",4)) {
1171                 cmd_list();
1172         }
1173
1174         else if (!strncasecmp(cmdbuf,"CHEK",4)) {
1175                 cmd_chek();
1176         }
1177
1178         else if (!strncasecmp(cmdbuf,"DELF",4)) {
1179                 cmd_delf(&cmdbuf[5]);
1180         }
1181
1182         else if (!strncasecmp(cmdbuf,"MOVF",4)) {
1183                 cmd_movf(&cmdbuf[5]);
1184         }
1185
1186         else if (!strncasecmp(cmdbuf,"NETF",4)) {
1187                 cmd_netf(&cmdbuf[5]);
1188         }
1189
1190         else if (!strncasecmp(cmdbuf,"OPEN",4)) {
1191                 cmd_open(&cmdbuf[5]);
1192         }
1193
1194         else if (!strncasecmp(cmdbuf,"CLOS",4)) {
1195                 cmd_clos();
1196         }
1197
1198         else if (!strncasecmp(cmdbuf,"UOPN",4)) {
1199                 cmd_uopn(&cmdbuf[5]);
1200         }
1201
1202         else if (!strncasecmp(cmdbuf,"UCLS",4)) {
1203                 cmd_ucls(&cmdbuf[5]);
1204         }
1205
1206         else if (!strncasecmp(cmdbuf,"READ",4)) {
1207                 cmd_read(&cmdbuf[5]);
1208         }
1209
1210         else if (!strncasecmp(cmdbuf,"WRIT",4)) {
1211                 cmd_writ(&cmdbuf[5]);
1212         }
1213
1214         else if (!strncasecmp(cmdbuf,"QUSR",4)) {
1215                 cmd_qusr(&cmdbuf[5]);
1216         }
1217
1218         else if (!strncasecmp(cmdbuf,"ECHO",4)) {
1219                 cmd_echo(&cmdbuf[5]);
1220         }
1221
1222         else if (!strncasecmp(cmdbuf,"OIMG",4)) {
1223                 cmd_oimg(&cmdbuf[5]);
1224         }
1225
1226         else if (!strncasecmp(cmdbuf,"MORE",4)) {
1227                 cmd_more();
1228         }
1229
1230         else if (!strncasecmp(cmdbuf,"NDOP",4)) {
1231                 cmd_ndop(&cmdbuf[5]);
1232         }
1233
1234         else if (!strncasecmp(cmdbuf,"NUOP",4)) {
1235                 cmd_nuop(&cmdbuf[5]);
1236         }
1237
1238         else if (!strncasecmp(cmdbuf,"LFLR",4)) {
1239                 cmd_lflr();
1240         }
1241
1242         else if (!strncasecmp(cmdbuf,"CFLR",4)) {
1243                 cmd_cflr(&cmdbuf[5]);
1244         }
1245
1246         else if (!strncasecmp(cmdbuf,"KFLR",4)) {
1247                 cmd_kflr(&cmdbuf[5]);
1248         }
1249
1250         else if (!strncasecmp(cmdbuf,"EFLR",4)) {
1251                 cmd_eflr(&cmdbuf[5]);
1252         }
1253
1254         else if (!strncasecmp(cmdbuf,"IDEN",4)) {
1255                 cmd_iden(&cmdbuf[5]);
1256         }
1257
1258         else if (!strncasecmp(cmdbuf,"IPGM",4)) {
1259                 cmd_ipgm(&cmdbuf[5]);
1260         }
1261
1262         else if (!strncasecmp(cmdbuf,"TERM",4)) {
1263                 cmd_term(&cmdbuf[5]);
1264         }
1265
1266         else if (!strncasecmp(cmdbuf,"DOWN",4)) {
1267                 cmd_down();
1268         }
1269
1270         else if (!strncasecmp(cmdbuf,"SCDN",4)) {
1271                 cmd_scdn(&cmdbuf[5]);
1272         }
1273
1274         else if (!strncasecmp(cmdbuf, "UIMG", 4)) {
1275                 cmd_uimg(&cmdbuf[5]);
1276         }
1277
1278         else if (!strncasecmp(cmdbuf, "TIME", 4)) {
1279                 cmd_time();
1280         }
1281
1282         else if (!strncasecmp(cmdbuf, "AGUP", 4)) {
1283                 cmd_agup(&cmdbuf[5]);
1284         }
1285
1286         else if (!strncasecmp(cmdbuf, "ASUP", 4)) {
1287                 cmd_asup(&cmdbuf[5]);
1288         }
1289
1290         else if (!strncasecmp(cmdbuf, "GPEX", 4)) {
1291                 cmd_gpex(&cmdbuf[5]);
1292         }
1293
1294         else if (!strncasecmp(cmdbuf, "SPEX", 4)) {
1295                 cmd_spex(&cmdbuf[5]);
1296         }
1297
1298         else if (!strncasecmp(cmdbuf, "CONF", 4)) {
1299                 cmd_conf(&cmdbuf[5]);
1300         }
1301
1302         else if (!strncasecmp(cmdbuf, "SEEN", 4)) {
1303                 cmd_seen(&cmdbuf[5]);
1304         }
1305
1306         else if (!strncasecmp(cmdbuf, "GTSN", 4)) {
1307                 cmd_gtsn(&cmdbuf[5]);
1308         }
1309
1310         else if (!strncasecmp(cmdbuf, "VIEW", 4)) {
1311                 cmd_view(&cmdbuf[5]);
1312         }
1313
1314         else if (!strncasecmp(cmdbuf, "ISME", 4)) {
1315                 cmd_isme(&cmdbuf[5]);
1316         }
1317
1318         else if (!DLoader_Exec_Cmd(cmdbuf)) {
1319                 cprintf("%d Unrecognized or unsupported command.\n",
1320                         ERROR + CMD_NOT_SUPPORTED);
1321                }
1322
1323         unbuffer_output();
1324
1325         /* Run any after-each-command routines registered by modules */
1326         PerformSessionHooks(EVT_CMD);
1327 }
1328
1329
1330 /*
1331  * This loop performs all asynchronous functions.
1332  */
1333 void do_async_loop(void) {
1334         PerformSessionHooks(EVT_ASYNC);
1335 }