citadel/citserver.c

   1 /*
   2  * Main source module for the Citadel server
   3  *
   4  * Copyright (c) 1987-2011 by the citadel.org team
   5  *
   6  * This program is open source software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License, version 3.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  */
  14
  15 #include "sysdep.h"
  16 #include <stdlib.h>
  17 #include <unistd.h>
  18 #include <stdio.h>
  19 #include <fcntl.h>
  20 #include <signal.h>
  21 #include <sys/types.h>
  22 #include <sys/stat.h>
  23
  24 #if TIME_WITH_SYS_TIME
  25 # include <sys/time.h>
  26 # include <time.h>
  27 #else
  28 # if HAVE_SYS_TIME_H
  29 #  include <sys/time.h>
  30 # else
  31 #  include <time.h>
  32 # endif
  33 #endif
  34
  35 #if HAVE_BACKTRACE
  36 #include <execinfo.h>
  37 #endif
  38
  39 #include <ctype.h>
  40 #include <string.h>
  41 #include <dirent.h>
  42 #include <errno.h>
  43 #include <limits.h>
  44 #include <netdb.h>
  45 #include <sys/types.h>
  46 #include <sys/socket.h>
  47 #include <netinet/in.h>
  48 #include <arpa/inet.h>
  49 #include <libcitadel.h>
  50 #include "citadel.h"
  51 #include "server.h"
  52 #include "sysdep_decls.h"
  53 #include "threads.h"
  54 #include "citserver.h"
  55 #include "config.h"
  56 #include "database.h"
  57 #include "housekeeping.h"
  58 #include "user_ops.h"
  59 #include "msgbase.h"
  60 #include "support.h"
  61 #include "locate_host.h"
  62 #include "room_ops.h"
  63 #include "file_ops.h"
  64 #include "control.h"
  65 #include "euidindex.h"
  66 #include "context.h"
  67 #include "svn_revision.h"
  68 #include "ctdl_module.h"
  69
  70 char *unique_session_numbers;
  71 int ScheduledShutdown = 0;
  72 time_t server_startup_time;
  73 int panic_fd;
  74 int openid_level_supported = 0;
  75
  76 /*
  77  * print the actual stack frame.
  78  */
  79 void cit_backtrace(void)
  80 {
  81 #ifdef HAVE_BACKTRACE
  82         void *stack_frames[50];
  83         size_t size, i;
  84         char **strings;
  85
  86
  87         size = backtrace(stack_frames, sizeof(stack_frames) / sizeof(void*));
  88         strings = backtrace_symbols(stack_frames, size);
  89         for (i = 0; i < size; i++) {
  90                 if (strings != NULL)
  91                         syslog(LOG_ALERT, "%s\n", strings[i]);
  92                 else
  93                         syslog(LOG_ALERT, "%p\n", stack_frames[i]);
  94         }
  95         free(strings);
  96 #endif
  97 }
  98
  99 void cit_oneline_backtrace(void)
 100 {
 101 #ifdef HAVE_BACKTRACE
 102         void *stack_frames[50];
 103         size_t size, i;
 104         char **strings;
 105         StrBuf *Buf;
 106
 107         size = backtrace(stack_frames, sizeof(stack_frames) / sizeof(void*));
 108         strings = backtrace_symbols(stack_frames, size);
 109         if (size > 0)
 110         {
 111                 Buf = NewStrBuf();
 112                 for (i = 1; i < size; i++) {
 113                         if (strings != NULL)
 114                                 StrBufAppendPrintf(Buf, "%s : ", strings[i]);
 115                         else
 116                                 StrBufAppendPrintf(Buf, "%p : ", stack_frames[i]);
 117                 }
 118                 free(strings);
 119                 syslog(LOG_ALERT, "%s\n", ChrPtr(Buf));
 120                 FreeStrBuf(&Buf);
 121         }
 122 #endif
 123 }
 124
 125 /*
 126  * print the actual stack frame.
 127  */
 128 void cit_panic_backtrace(int SigNum)
 129 {
 130 #ifdef HAVE_BACKTRACE
 131         void *stack_frames[10];
 132         size_t size, i;
 133         char **strings;
 134
 135         printf("caught signal 11\n");
 136         size = backtrace(stack_frames, sizeof(stack_frames) / sizeof(void*));
 137         strings = backtrace_symbols(stack_frames, size);
 138         for (i = 0; i < size; i++) {
 139                 if (strings != NULL)
 140                         syslog(LOG_ALERT, "%s\n", strings[i]);
 141                 else
 142                         syslog(LOG_ALERT, "%p\n", stack_frames[i]);
 143         }
 144         free(strings);
 145 #endif
 146         exit(-1);
 147 }
 148
 149 /*
 150  * Various things that need to be initialized at startup
 151  */
 152 void master_startup(void) {
 153         struct timeval tv;
 154         unsigned int seed;
 155         FILE *urandom;
 156         struct ctdlroom qrbuf;
 157         int rv;
 158
 159         syslog(LOG_DEBUG, "master_startup() started\n");
 160         time(&server_startup_time);
 161         get_config();
 162
 163         syslog(LOG_INFO, "Opening databases\n");
 164         open_databases();
 165         check_ref_counts();
 166
 167         syslog(LOG_INFO, "Creating base rooms (if necessary)\n");
 168         CtdlCreateRoom(config.c_baseroom,       0, "", 0, 1, 0, VIEW_BBS);
 169         CtdlCreateRoom(AIDEROOM,                3, "", 0, 1, 0, VIEW_BBS);
 170         CtdlCreateRoom(SYSCONFIGROOM,           3, "", 0, 1, 0, VIEW_BBS);
 171         CtdlCreateRoom(config.c_twitroom,       0, "", 0, 1, 0, VIEW_BBS);
 172
 173         /* The "Local System Configuration" room doesn't need to be visible */
 174         if (CtdlGetRoomLock(&qrbuf, SYSCONFIGROOM) == 0) {
 175                 qrbuf.QRflags2 |= QR2_SYSTEM;
 176                 CtdlPutRoomLock(&qrbuf);
 177         }
 178
 179         /* Aide needs to be public postable, else we're not RFC conformant. */
 180         if (CtdlGetRoomLock(&qrbuf, AIDEROOM) == 0) {
 181                 qrbuf.QRflags2 |= QR2_SMTP_PUBLIC;
 182                 CtdlPutRoomLock(&qrbuf);
 183         }
 184
 185         syslog(LOG_INFO, "Seeding the pseudo-random number generator...\n");
 186         urandom = fopen("/dev/urandom", "r");
 187         if (urandom != NULL) {
 188                 rv = fread(&seed, sizeof seed, 1, urandom);
 189                 if (rv == -1)
 190                         syslog(LOG_EMERG, "failed to read random seed: %s\n",
 191                                strerror(errno));
 192                 fclose(urandom);
 193         }
 194         else {
 195                 gettimeofday(&tv, NULL);
 196                 seed = tv.tv_usec;
 197         }
 198         srand(seed);
 199         srandom(seed);
 200
 201         put_config();
 202
 203         syslog(LOG_DEBUG, "master_startup() finished\n");
 204 }
 205
 206
 207 /*
 208  * Cleanup routine to be called when the server is shutting down.
 209  */
 210 void master_cleanup(int exitcode) {
 211         struct CleanupFunctionHook *fcn;
 212         static int already_cleaning_up = 0;
 213
 214         if (already_cleaning_up) while(1) usleep(1000000);
 215         already_cleaning_up = 1;
 216
 217         /* Run any cleanup routines registered by loadable modules */
 218         for (fcn = CleanupHookTable; fcn != NULL; fcn = fcn->next) {
 219                 (*fcn->h_function_pointer)();
 220         }
 221
 222         /* Close the AdjRefCount queue file */
 223         AdjRefCount(-1, 0);
 224
 225         /* Do system-dependent stuff */
 226         sysdep_master_cleanup();
 227
 228         /* Close databases */
 229         syslog(LOG_INFO, "Closing databases\n");
 230         close_databases();
 231
 232         /* If the operator requested a halt but not an exit, halt here. */
 233         if (shutdown_and_halt) {
 234                 syslog(LOG_NOTICE, "citserver: Halting server without exiting.\n");
 235                 fflush(stdout); fflush(stderr);
 236                 while(1) {
 237                         sleep(32767);
 238                 }
 239         }
 240
 241         release_control();
 242
 243         /* Now go away. */
 244         syslog(LOG_NOTICE, "citserver: Exiting with status %d\n", exitcode);
 245         fflush(stdout); fflush(stderr);
 246
 247         if (restart_server != 0)
 248                 exit(1);
 249         if ((running_as_daemon != 0) && ((exitcode == 0) ))
 250                 exitcode = CTDLEXIT_SHUTDOWN;
 251         exit(exitcode);
 252 }
 253
 254
 255
 256 /*
 257  * returns an asterisk if there are any instant messages waiting,
 258  * space otherwise.
 259  */
 260 char CtdlCheckExpress(void) {
 261         if (CC->FirstExpressMessage == NULL) {
 262                 return(' ');
 263         }
 264         else {
 265                 return('*');
 266         }
 267 }
 268
 269
 270 /*
 271  * Check originating host against the public_clients file.  This determines
 272  * whether the client is allowed to change the hostname for this session
 273  * (for example, to show the location of the user rather than the location
 274  * of the client).
 275  */
 276 int is_public_client(void)
 277 {
 278         char buf[1024];
 279         char addrbuf[1024];
 280         FILE *fp;
 281         int i;
 282         char *public_clientspos;
 283         char *public_clientsend;
 284         char *paddr = NULL;
 285         struct stat statbuf;
 286         static time_t pc_timestamp = 0;
 287         static char public_clients[SIZ];
 288         static char public_clients_file[SIZ];
 289
 290 #define LOCALHOSTSTR "127.0.0.1"
 291
 292         snprintf(public_clients_file, sizeof public_clients_file, "%s/public_clients", ctdl_etc_dir);
 293
 294         /*
 295          * Check the time stamp on the public_clients file.  If it's been
 296          * updated since the last time we were here (or if this is the first
 297          * time we've been through the loop), read its contents and learn
 298          * the IP addresses of the listed hosts.
 299          */
 300         if (stat(public_clients_file, &statbuf) != 0) {
 301                 /* No public_clients file exists, so bail out */
 302                 syslog(LOG_WARNING, "Warning: '%s' does not exist\n",
 303                                 public_clients_file);
 304                 return(0);
 305         }
 306
 307         if (statbuf.st_mtime > pc_timestamp) {
 308                 begin_critical_section(S_PUBLIC_CLIENTS);
 309                 syslog(LOG_INFO, "Loading %s\n", public_clients_file);
 310
 311                 public_clientspos = &public_clients[0];
 312                 public_clientsend = public_clientspos + SIZ;
 313                 safestrncpy(public_clientspos, LOCALHOSTSTR, sizeof public_clients);
 314                 public_clientspos += sizeof(LOCALHOSTSTR) - 1;
 315
 316                 if (hostname_to_dotted_quad(addrbuf, config.c_fqdn) == 0) {
 317                         *(public_clientspos++) = '|';
 318                         paddr = &addrbuf[0];
 319                         while (!IsEmptyStr (paddr) &&
 320                                (public_clientspos < public_clientsend))
 321                                 *(public_clientspos++) = *(paddr++);
 322                 }
 323
 324                 fp = fopen(public_clients_file, "r");
 325                 if (fp != NULL)
 326                         while ((fgets(buf, sizeof buf, fp)!=NULL) &&
 327                                (public_clientspos < public_clientsend)){
 328                                 char *ptr;
 329                                 ptr = buf;
 330                                 while (!IsEmptyStr(ptr)) {
 331                                         if (*ptr == '#') {
 332                                                 *ptr = 0;
 333                                                 break;
 334                                         }
 335                                 else ptr++;
 336                                 }
 337                                 ptr--;
 338                                 while (ptr>buf && isspace(*ptr)) {
 339                                         *(ptr--) = 0;
 340                                 }
 341                                 if (hostname_to_dotted_quad(addrbuf, buf) == 0) {
 342                                         *(public_clientspos++) = '|';
 343                                         paddr = addrbuf;
 344                                         while (!IsEmptyStr(paddr) &&
 345                                                (public_clientspos < public_clientsend)){
 346                                                 *(public_clientspos++) = *(paddr++);
 347                                         }
 348                                 }
 349                         }
 350                 if (fp != NULL) fclose(fp);
 351                 pc_timestamp = time(NULL);
 352                 end_critical_section(S_PUBLIC_CLIENTS);
 353         }
 354
 355         syslog(LOG_DEBUG, "Checking whether %s is a local or public client\n",
 356                 CC->cs_addr);
 357         for (i=0; i<num_parms(public_clients); ++i) {
 358                 extract_token(addrbuf, public_clients, i, '|', sizeof addrbuf);
 359                 if (!strcasecmp(CC->cs_addr, addrbuf)) {
 360                         syslog(LOG_DEBUG, "... yes its local.\n");
 361                         return(1);
 362                 }
 363         }
 364
 365         /* No hits.  This is not a public client. */
 366         syslog(LOG_DEBUG, "... no it isn't.\n");
 367         return(0);
 368 }
 369
 370
 371
 372 /*
 373  * help_subst()  -  support routine for help file viewer
 374  */
 375 void help_subst(char *strbuf, char *source, char *dest)
 376 {
 377         char workbuf[SIZ];
 378         int p;
 379
 380         while (p = pattern2(strbuf, source), (p >= 0)) {
 381                 strcpy(workbuf, &strbuf[p + strlen(source)]);
 382                 strcpy(&strbuf[p], dest);
 383                 strcat(strbuf, workbuf);
 384         }
 385 }
 386
 387 void do_help_subst(char *buffer)
 388 {
 389         char buf2[16];
 390
 391         help_subst(buffer, "^nodename", config.c_nodename);
 392         help_subst(buffer, "^humannode", config.c_humannode);
 393         help_subst(buffer, "^fqdn", config.c_fqdn);
 394         help_subst(buffer, "^username", CC->user.fullname);
 395         snprintf(buf2, sizeof buf2, "%ld", CC->user.usernum);
 396         help_subst(buffer, "^usernum", buf2);
 397         help_subst(buffer, "^sysadm", config.c_sysadm);
 398         help_subst(buffer, "^variantname", CITADEL);
 399         snprintf(buf2, sizeof buf2, "%d", config.c_maxsessions);
 400         help_subst(buffer, "^maxsessions", buf2);
 401         help_subst(buffer, "^bbsdir", ctdl_message_dir);
 402 }
 403
 404
 405 typedef const char *ccharp;
 406 /*
 407  * display system messages or help
 408  */
 409 void cmd_mesg(char *mname)
 410 {
 411         FILE *mfp;
 412         char targ[256];
 413         char buf[256];
 414         char buf2[256];
 415         char *dirs[2];
 416         DIR *dp;
 417         struct dirent *d;
 418
 419         extract_token(buf, mname, 0, '|', sizeof buf);
 420
 421         dirs[0] = strdup(ctdl_message_dir);
 422         dirs[1] = strdup(ctdl_hlp_dir);
 423
 424         snprintf(buf2, sizeof buf2, "%s.%d.%d",
 425                 buf, CC->cs_clientdev, CC->cs_clienttyp);
 426
 427         /* If the client requested "?" then produce a listing */
 428         if (!strcmp(buf, "?")) {
 429                 cprintf("%d %s\n", LISTING_FOLLOWS, buf);
 430                 dp = opendir(dirs[1]);
 431                 if (dp != NULL) {
 432                         while (d = readdir(dp), d != NULL) {
 433                                 if (d->d_name[0] != '.') {
 434                                         cprintf(" %s\n", d->d_name);
 435                                 }
 436                         }
 437                         closedir(dp);
 438                 }
 439                 cprintf("000\n");
 440                 free(dirs[0]);
 441                 free(dirs[1]);
 442                 return;
 443         }
 444
 445         /* Otherwise, look for the requested file by name. */
 446         else {
 447                 mesg_locate(targ, sizeof targ, buf2, 2, (const ccharp*)dirs);
 448                 if (IsEmptyStr(targ)) {
 449                         snprintf(buf2, sizeof buf2, "%s.%d",
 450                                                         buf, CC->cs_clientdev);
 451                         mesg_locate(targ, sizeof targ, buf2, 2,
 452                                     (const ccharp*)dirs);
 453                         if (IsEmptyStr(targ)) {
 454                                 mesg_locate(targ, sizeof targ, buf, 2,
 455                                             (const ccharp*)dirs);
 456                         }
 457                 }
 458         }
 459
 460         free(dirs[0]);
 461         free(dirs[1]);
 462
 463         if (IsEmptyStr(targ)) {
 464                 cprintf("%d '%s' not found.  (Searching in %s and %s)\n",
 465                         ERROR + FILE_NOT_FOUND,
 466                         mname,
 467                         ctdl_message_dir,
 468                         ctdl_hlp_dir
 469                 );
 470                 return;
 471         }
 472
 473         mfp = fopen(targ, "r");
 474         if (mfp==NULL) {
 475                 cprintf("%d Cannot open '%s': %s\n",
 476                         ERROR + INTERNAL_ERROR, targ, strerror(errno));
 477                 return;
 478         }
 479         cprintf("%d %s\n", LISTING_FOLLOWS,buf);
 480
 481         while (fgets(buf, (sizeof buf - 1), mfp) != NULL) {
 482                 buf[strlen(buf)-1] = 0;
 483                 do_help_subst(buf);
 484                 cprintf("%s\n",buf);
 485         }
 486
 487         fclose(mfp);
 488         cprintf("000\n");
 489 }
 490
 491
 492 /*
 493  * enter system messages or help
 494  */
 495 void cmd_emsg(char *mname)
 496 {
 497         FILE *mfp;
 498         char targ[256];
 499         char buf[256];
 500         char *dirs[2];
 501         int a;
 502
 503         unbuffer_output();
 504
 505         if (CtdlAccessCheck(ac_aide)) return;
 506
 507         extract_token(buf, mname, 0, '|', sizeof buf);
 508         for (a=0; !IsEmptyStr(&buf[a]); ++a) {          /* security measure */
 509                 if (buf[a] == '/') buf[a] = '.';
 510         }
 511
 512         dirs[0] = strdup(ctdl_message_dir);
 513         dirs[1] = strdup(ctdl_hlp_dir);
 514
 515         mesg_locate(targ, sizeof targ, buf, 2, (const ccharp*)dirs);
 516         free(dirs[0]);
 517         free(dirs[1]);
 518
 519         if (IsEmptyStr(targ)) {
 520                 snprintf(targ, sizeof targ,
 521                                  "%s/%s",
 522                                  ctdl_hlp_dir, buf);
 523         }
 524
 525         mfp = fopen(targ,"w");
 526         if (mfp==NULL) {
 527                 cprintf("%d Cannot open '%s': %s\n",
 528                         ERROR + INTERNAL_ERROR, targ, strerror(errno));
 529                 return;
 530         }
 531         cprintf("%d %s\n", SEND_LISTING, targ);
 532
 533         while (client_getln(buf, sizeof buf) >=0 && strcmp(buf, "000")) {
 534                 fprintf(mfp, "%s\n", buf);
 535         }
 536
 537         fclose(mfp);
 538 }
 539
 540
 541 /* Don't show the names of private rooms unless the viewing
 542  * user also knows the rooms.
 543  */
 544 void GenerateRoomDisplay(char *real_room,
 545                         CitContext *viewed,
 546                         CitContext *viewer) {
 547
 548         int ra;
 549
 550         strcpy(real_room, viewed->room.QRname);
 551         if (viewed->room.QRflags & QR_MAILBOX) {
 552                 strcpy(real_room, &real_room[11]);
 553         }
 554         if (viewed->room.QRflags & QR_PRIVATE) {
 555                 CtdlRoomAccess(&viewed->room, &viewer->user, &ra, NULL);
 556                 if ( (ra & UA_KNOWN) == 0) {
 557                         strcpy(real_room, " ");
 558                 }
 559         }
 560
 561         if (viewed->cs_flags & CS_CHAT) {
 562                 while (strlen(real_room) < 14) {
 563                         strcat(real_room, " ");
 564                 }
 565                 strcpy(&real_room[14], "<chat>");
 566         }
 567
 568 }
 569
 570 /*
 571  * Convenience function.
 572  */
 573 int CtdlAccessCheck(int required_level) {
 574
 575         if (CC->internal_pgm) return(0);
 576         if (required_level >= ac_internal) {
 577                 cprintf("%d This is not a user-level command.\n",
 578                         ERROR + HIGHER_ACCESS_REQUIRED);
 579                 return(-1);
 580         }
 581
 582         if ((required_level >= ac_logged_in_or_guest) && (CC->logged_in == 0) && (!config.c_guest_logins)) {
 583                 cprintf("%d Not logged in.\n", ERROR + NOT_LOGGED_IN);
 584                 return(-1);
 585         }
 586
 587         if ((required_level >= ac_logged_in) && (CC->logged_in == 0)) {
 588                 cprintf("%d Not logged in.\n", ERROR + NOT_LOGGED_IN);
 589                 return(-1);
 590         }
 591
 592         if (CC->user.axlevel >= AxAideU) return(0);
 593         if (required_level >= ac_aide) {
 594                 cprintf("%d This command requires Admin access.\n",
 595                         ERROR + HIGHER_ACCESS_REQUIRED);
 596                 return(-1);
 597         }
 598
 599         if (is_room_aide()) return(0);
 600         if (required_level >= ac_room_aide) {
 601                 cprintf("%d This command requires Admin or Room Admin access.\n",
 602                         ERROR + HIGHER_ACCESS_REQUIRED);
 603                 return(-1);
 604         }
 605
 606         /* shhh ... succeed quietly */
 607         return(0);
 608 }
 609
 610
 611
 612
 613
 614
 615 /*
 616  * Shut down the server
 617  */
 618 void cmd_down(char *argbuf) {
 619         char *Reply ="%d Shutting down server.  Goodbye.\n";
 620
 621         if (CtdlAccessCheck(ac_aide)) return;
 622
 623         if (!IsEmptyStr(argbuf))
 624         {
 625                 int state = CIT_OK;
 626                 restart_server = extract_int(argbuf, 0);
 627
 628                 if (restart_server > 0)
 629                 {
 630                         Reply = "%d citserver will now shut down and automatically restart.\n";
 631                 }
 632                 if ((restart_server > 0) && !running_as_daemon)
 633                 {
 634                         syslog(LOG_ERR, "The user requested restart, but not running as daemon! Geronimooooooo!\n");
 635                         Reply = "%d Warning: citserver is not running in daemon mode and is therefore unlikely to restart automatically.\n";
 636                         state = ERROR;
 637                 }
 638                 cprintf(Reply, state);
 639         }
 640         else
 641         {
 642                 cprintf(Reply, CIT_OK + SERVER_SHUTTING_DOWN);
 643         }
 644         CC->kill_me = KILLME_SERVER_SHUTTING_DOWN;
 645         server_shutting_down = 1;
 646 }
 647
 648
 649 /*
 650  * Halt the server without exiting the server process.
 651  */
 652 void cmd_halt(char *argbuf) {
 653
 654         if (CtdlAccessCheck(ac_aide)) return;
 655
 656         cprintf("%d Halting server.  Goodbye.\n", CIT_OK);
 657         server_shutting_down = 1;
 658         shutdown_and_halt = 1;
 659 }
 660
 661
 662 /*
 663  * Schedule or cancel a server shutdown
 664  */
 665 void cmd_scdn(char *argbuf)
 666 {
 667         int new_state;
 668         int state = CIT_OK;
 669         char *Reply = "%d %d\n";
 670
 671         if (CtdlAccessCheck(ac_aide)) return;
 672
 673         new_state = extract_int(argbuf, 0);
 674         if ((new_state == 2) || (new_state == 3))
 675         {
 676                 restart_server = 1;
 677                 if (!running_as_daemon)
 678                 {
 679                         syslog(LOG_ERR, "The user requested restart, but not running as deamon! Geronimooooooo!\n");
 680                         Reply = "%d %d Warning, not running in deamon mode. maybe we will come up again, but don't lean on it.\n";
 681                         state = ERROR;
 682                 }
 683
 684                 restart_server = extract_int(argbuf, 0);
 685                 new_state -= 2;
 686         }
 687         if ((new_state == 0) || (new_state == 1)) {
 688                 ScheduledShutdown = new_state;
 689         }
 690         cprintf(Reply, state, ScheduledShutdown);
 691 }
 692
 693
 694
 695 /*
 696  * Back-end function for starting a session
 697  */
 698 void begin_session(CitContext *con)
 699 {
 700         /*
 701          * Initialize some variables specific to our context.
 702          */
 703         con->logged_in = 0;
 704         con->internal_pgm = 0;
 705         con->download_fp = NULL;
 706         con->upload_fp = NULL;
 707         con->cached_msglist = NULL;
 708         con->cached_num_msgs = 0;
 709         con->FirstExpressMessage = NULL;
 710         time(&con->lastcmd);
 711         time(&con->lastidle);
 712         strcpy(con->lastcmdname, "    ");
 713         strcpy(con->cs_clientname, "(unknown)");
 714         strcpy(con->curr_user, NLI);
 715         *con->net_node = '\0';
 716         *con->fake_username = '\0';
 717         *con->fake_hostname = '\0';
 718         *con->fake_roomname = '\0';
 719         *con->cs_clientinfo = '\0';
 720         safestrncpy(con->cs_host, config.c_fqdn, sizeof con->cs_host);
 721         safestrncpy(con->cs_addr, "", sizeof con->cs_addr);
 722         con->cs_UDSclientUID = -1;
 723         con->cs_host[sizeof con->cs_host - 1] = 0;
 724         if (!CC->is_local_socket) {
 725                 locate_host(con->cs_host, sizeof con->cs_host,
 726                         con->cs_addr, sizeof con->cs_addr,
 727                         con->client_socket
 728                 );
 729         }
 730         else {
 731                 con->cs_host[0] = 0;
 732                 con->cs_addr[0] = 0;
 733 #ifdef HAVE_STRUCT_UCRED
 734                 {
 735                         /* as http://www.wsinnovations.com/softeng/articles/uds.html told us... */
 736                         struct ucred credentials;
 737                         socklen_t ucred_length = sizeof(struct ucred);
 738
 739                         /*fill in the user data structure */
 740                         if(getsockopt(con->client_socket, SOL_SOCKET, SO_PEERCRED, &credentials, &ucred_length)) {
 741                                 syslog(LOG_NOTICE, "could obtain credentials from unix domain socket");
 742
 743                         }
 744                         else {
 745                                 /* the process ID of the process on the other side of the socket */
 746                                 /* credentials.pid; */
 747
 748                                 /* the effective UID of the process on the other side of the socket  */
 749                                 con->cs_UDSclientUID = credentials.uid;
 750
 751                                 /* the effective primary GID of the process on the other side of the socket */
 752                                 /* credentials.gid; */
 753
 754                                 /* To get supplemental groups, we will have to look them up in our account
 755                                    database, after a reverse lookup on the UID to get the account name.
 756                                    We can take this opportunity to check to see if this is a legit account.
 757                                 */
 758                                 snprintf(con->cs_clientinfo, sizeof(con->cs_clientinfo),
 759                                          "PID: "F_PID_T"; UID: "F_UID_T"; GID: "F_XPID_T" ",
 760                                          credentials.pid,
 761                                          credentials.uid,
 762                                          credentials.gid);
 763                         }
 764                 }
 765 #endif
 766         }
 767         con->cs_flags = 0;
 768         con->upload_type = UPL_FILE;
 769         con->dl_is_net = 0;
 770
 771         con->nologin = 0;
 772         if (((config.c_maxsessions > 0)&&(num_sessions > config.c_maxsessions)) || CtdlWantSingleUser()) {
 773                 con->nologin = 1;
 774         }
 775
 776         if (!CC->is_local_socket) {
 777                 syslog(LOG_NOTICE, "Session (%s) started from %s (%s).\n", con->ServiceName, con->cs_host, con->cs_addr);
 778         }
 779         else {
 780                 syslog(LOG_NOTICE, "Session (%s) started via local socket UID:%d.\n", con->ServiceName, con->cs_UDSclientUID);
 781         }
 782
 783         /* Run any session startup routines registered by loadable modules */
 784         PerformSessionHooks(EVT_START);
 785 }
 786
 787
 788 void citproto_begin_session() {
 789         if (CC->nologin==1) {
 790                 cprintf("%d %s: Too many users are already online (maximum is %d)\n",
 791                         ERROR + MAX_SESSIONS_EXCEEDED,
 792                         config.c_nodename, config.c_maxsessions
 793                 );
 794                 CC->kill_me = KILLME_MAX_SESSIONS_EXCEEDED;
 795         }
 796         else {
 797                 cprintf("%d %s Citadel server ready.\n", CIT_OK, config.c_nodename);
 798                 CC->can_receive_im = 1;
 799         }
 800 }
 801
 802
 803 void citproto_begin_admin_session() {
 804         CC->internal_pgm = 1;
 805         cprintf("%d %s Citadel server ADMIN CONNECTION ready.\n", CIT_OK, config.c_nodename);
 806 }
 807
 808
 809
 810
 811 /*
 812  * This loop recognizes all server commands.
 813  */
 814 void do_command_loop(void) {
 815         char cmdbuf[SIZ];
 816
 817         time(&CC->lastcmd);
 818         memset(cmdbuf, 0, sizeof cmdbuf); /* Clear it, just in case */
 819         if (client_getln(cmdbuf, sizeof cmdbuf) < 1) {
 820                 syslog(LOG_ERR, "Citadel client disconnected: ending session.\n");
 821                 CC->kill_me = KILLME_CLIENT_DISCONNECTED;
 822                 return;
 823         }
 824
 825         /* Log the server command, but don't show passwords... */
 826         if ( (strncasecmp(cmdbuf, "PASS", 4)) && (strncasecmp(cmdbuf, "SETP", 4)) ) {
 827                 syslog(LOG_INFO, "[%d][%s(%ld)] %s",
 828                         CC->cs_pid, CC->curr_user, CC->user.usernum, cmdbuf
 829                 );
 830         }
 831         else {
 832                 syslog(LOG_INFO, "[%d][%s(%ld)] <password command hidden from log>",
 833                         CC->cs_pid, CC->curr_user, CC->user.usernum
 834                 );
 835         }
 836
 837         buffer_output();
 838
 839         /*
 840          * Let other clients see the last command we executed, and
 841          * update the idle time, but not NOOP, QNOP, PEXP, GEXP, RWHO, or TIME.
 842          */
 843         if ( (strncasecmp(cmdbuf, "NOOP", 4))
 844            && (strncasecmp(cmdbuf, "QNOP", 4))
 845            && (strncasecmp(cmdbuf, "PEXP", 4))
 846            && (strncasecmp(cmdbuf, "GEXP", 4))
 847            && (strncasecmp(cmdbuf, "RWHO", 4))
 848            && (strncasecmp(cmdbuf, "TIME", 4)) ) {
 849                 strcpy(CC->lastcmdname, "    ");
 850                 safestrncpy(CC->lastcmdname, cmdbuf, sizeof(CC->lastcmdname));
 851                 time(&CC->lastidle);
 852         }
 853
 854         if ((strncasecmp(cmdbuf, "ENT0", 4))
 855            && (strncasecmp(cmdbuf, "MESG", 4))
 856            && (strncasecmp(cmdbuf, "MSGS", 4)))
 857         {
 858            CC->cs_flags &= ~CS_POSTING;
 859         }
 860
 861         if (!DLoader_Exec_Cmd(cmdbuf)) {
 862                 cprintf("%d Unrecognized or unsupported command.\n", ERROR + CMD_NOT_SUPPORTED);
 863         }
 864
 865         unbuffer_output();
 866
 867         /* Run any after-each-command routines registered by modules */
 868         PerformSessionHooks(EVT_CMD);
 869 }
 870
 871
 872 /*
 873  * This loop performs all asynchronous functions.
 874  */
 875 void do_async_loop(void) {
 876         PerformSessionHooks(EVT_ASYNC);
 877 }
 878
 879
 880 /*****************************************************************************/
 881 /*                      MODULE INITIALIZATION STUFF                          */
 882 /*****************************************************************************/
 883
 884 CTDL_MODULE_INIT(citserver)
 885 {
 886         if (!threading) {
 887
 888                 CtdlRegisterProtoHook(cmd_mesg, "MESG", "fetch system banners");
 889                 CtdlRegisterProtoHook(cmd_emsg, "EMSG", "submit system banners");
 890 ;
 891                 CtdlRegisterProtoHook(cmd_down, "DOWN", "perform a server shutdown");
 892                 CtdlRegisterProtoHook(cmd_halt, "HALT", "halt the server without exiting the server process");
 893                 CtdlRegisterProtoHook(cmd_scdn, "SCDN", "schedule or cancel a server shutdown");
 894         }
 895         /* return our id for the Log */
 896         return "citserver";
 897 }