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  * cmd_info()  -  tell the client about this server
 258  */
 259 void cmd_info(char *cmdbuf) {
 260         cprintf("%d Server info:\n", LISTING_FOLLOWS);
 261         cprintf("%d\n", CC->cs_pid);
 262         cprintf("%s\n", config.c_nodename);
 263         cprintf("%s\n", config.c_humannode);
 264         cprintf("%s\n", config.c_fqdn);
 265         cprintf("%s\n", CITADEL);
 266         cprintf("%d\n", REV_LEVEL);
 267         cprintf("%s\n", config.c_site_location);
 268         cprintf("%s\n", config.c_sysadm);
 269         cprintf("%d\n", SERVER_TYPE);
 270         cprintf("%s\n", config.c_moreprompt);
 271         cprintf("1\n"); /* 1 = yes, this system supports floors */
 272         cprintf("1\n"); /* 1 = we support the extended paging options */
 273         cprintf("\n");  /* nonce no longer supported */
 274         cprintf("1\n"); /* 1 = yes, this system supports the QNOP command */
 275
 276 #ifdef HAVE_LDAP
 277         cprintf("1\n"); /* 1 = yes, this server is LDAP-enabled */
 278 #else
 279         cprintf("0\n"); /* 1 = no, this server is not LDAP-enabled */
 280 #endif
 281
 282         if ((config.c_auth_mode == AUTHMODE_NATIVE) &&
 283             (config.c_disable_newu == 0))
 284         {
 285                 cprintf("%d\n", config.c_disable_newu);
 286         }
 287         else {
 288                 cprintf("1\n"); /* "create new user" does not work with non-native auth modes */
 289         }
 290
 291         cprintf("%s\n", config.c_default_cal_zone);
 292
 293         /* thread load averages -- temporarily disabled during refactoring of this code */
 294         cprintf("0\n");         /* load average */
 295         cprintf("0\n");         /* worker average */
 296         cprintf("0\n");         /* thread count */
 297
 298         cprintf("1\n");         /* yes, Sieve mail filtering is supported */
 299         cprintf("%d\n", config.c_enable_fulltext);
 300         cprintf("%s\n", svn_revision());
 301
 302         if (config.c_auth_mode == AUTHMODE_NATIVE) {
 303                 cprintf("%d\n", openid_level_supported); /* OpenID is enabled when using native auth */
 304         }
 305         else {
 306                 cprintf("0\n"); /* OpenID is disabled when using non-native auth */
 307         }
 308
 309         cprintf("%d\n", config.c_guest_logins);
 310
 311         cprintf("000\n");
 312 }
 313
 314
 315 /*
 316  * returns an asterisk if there are any instant messages waiting,
 317  * space otherwise.
 318  */
 319 char CtdlCheckExpress(void) {
 320         if (CC->FirstExpressMessage == NULL) {
 321                 return(' ');
 322         }
 323         else {
 324                 return('*');
 325         }
 326 }
 327
 328 void cmd_time(char *argbuf)
 329 {
 330    time_t tv;
 331    struct tm tmp;
 332
 333    tv = time(NULL);
 334    localtime_r(&tv, &tmp);
 335
 336    /* timezone and daylight global variables are not portable. */
 337 #ifdef HAVE_STRUCT_TM_TM_GMTOFF
 338    cprintf("%d %ld|%ld|%d|%ld\n", CIT_OK, (long)tv, tmp.tm_gmtoff, tmp.tm_isdst, server_startup_time);
 339 #else
 340    cprintf("%d %ld|%ld|%d|%ld\n", CIT_OK, (long)tv, timezone, tmp.tm_isdst, server_startup_time);
 341 #endif
 342 }
 343
 344
 345 /*
 346  * Check originating host against the public_clients file.  This determines
 347  * whether the client is allowed to change the hostname for this session
 348  * (for example, to show the location of the user rather than the location
 349  * of the client).
 350  */
 351 int is_public_client(void)
 352 {
 353         char buf[1024];
 354         char addrbuf[1024];
 355         FILE *fp;
 356         int i;
 357         char *public_clientspos;
 358         char *public_clientsend;
 359         char *paddr = NULL;
 360         struct stat statbuf;
 361         static time_t pc_timestamp = 0;
 362         static char public_clients[SIZ];
 363         static char public_clients_file[SIZ];
 364
 365 #define LOCALHOSTSTR "127.0.0.1"
 366
 367         snprintf(public_clients_file, sizeof public_clients_file, "%s/public_clients", ctdl_etc_dir);
 368
 369         /*
 370          * Check the time stamp on the public_clients file.  If it's been
 371          * updated since the last time we were here (or if this is the first
 372          * time we've been through the loop), read its contents and learn
 373          * the IP addresses of the listed hosts.
 374          */
 375         if (stat(public_clients_file, &statbuf) != 0) {
 376                 /* No public_clients file exists, so bail out */
 377                 syslog(LOG_WARNING, "Warning: '%s' does not exist\n",
 378                                 public_clients_file);
 379                 return(0);
 380         }
 381
 382         if (statbuf.st_mtime > pc_timestamp) {
 383                 begin_critical_section(S_PUBLIC_CLIENTS);
 384                 syslog(LOG_INFO, "Loading %s\n", public_clients_file);
 385
 386                 public_clientspos = &public_clients[0];
 387                 public_clientsend = public_clientspos + SIZ;
 388                 safestrncpy(public_clientspos, LOCALHOSTSTR, sizeof public_clients);
 389                 public_clientspos += sizeof(LOCALHOSTSTR) - 1;
 390
 391                 if (hostname_to_dotted_quad(addrbuf, config.c_fqdn) == 0) {
 392                         *(public_clientspos++) = '|';
 393                         paddr = &addrbuf[0];
 394                         while (!IsEmptyStr (paddr) &&
 395                                (public_clientspos < public_clientsend))
 396                                 *(public_clientspos++) = *(paddr++);
 397                 }
 398
 399                 fp = fopen(public_clients_file, "r");
 400                 if (fp != NULL)
 401                         while ((fgets(buf, sizeof buf, fp)!=NULL) &&
 402                                (public_clientspos < public_clientsend)){
 403                                 char *ptr;
 404                                 ptr = buf;
 405                                 while (!IsEmptyStr(ptr)) {
 406                                         if (*ptr == '#') {
 407                                                 *ptr = 0;
 408                                                 break;
 409                                         }
 410                                 else ptr++;
 411                                 }
 412                                 ptr--;
 413                                 while (ptr>buf && isspace(*ptr)) {
 414                                         *(ptr--) = 0;
 415                                 }
 416                                 if (hostname_to_dotted_quad(addrbuf, buf) == 0) {
 417                                         *(public_clientspos++) = '|';
 418                                         paddr = addrbuf;
 419                                         while (!IsEmptyStr(paddr) &&
 420                                                (public_clientspos < public_clientsend)){
 421                                                 *(public_clientspos++) = *(paddr++);
 422                                         }
 423                                 }
 424                         }
 425                 if (fp != NULL) fclose(fp);
 426                 pc_timestamp = time(NULL);
 427                 end_critical_section(S_PUBLIC_CLIENTS);
 428         }
 429
 430         syslog(LOG_DEBUG, "Checking whether %s is a local or public client\n",
 431                 CC->cs_addr);
 432         for (i=0; i<num_parms(public_clients); ++i) {
 433                 extract_token(addrbuf, public_clients, i, '|', sizeof addrbuf);
 434                 if (!strcasecmp(CC->cs_addr, addrbuf)) {
 435                         syslog(LOG_DEBUG, "... yes its local.\n");
 436                         return(1);
 437                 }
 438         }
 439
 440         /* No hits.  This is not a public client. */
 441         syslog(LOG_DEBUG, "... no it isn't.\n");
 442         return(0);
 443 }
 444
 445
 446 /*
 447  * the client is identifying itself to the server
 448  */
 449 void cmd_iden(char *argbuf)
 450 {
 451         int dev_code;
 452         int cli_code;
 453         int rev_level;
 454         char desc[128];
 455         char from_host[128];
 456
 457         if (num_parms(argbuf)<4) {
 458                 cprintf("%d usage error\n", ERROR + ILLEGAL_VALUE);
 459                 return;
 460         }
 461
 462         dev_code = extract_int(argbuf,0);
 463         cli_code = extract_int(argbuf,1);
 464         rev_level = extract_int(argbuf,2);
 465         extract_token(desc, argbuf, 3, '|', sizeof desc);
 466
 467         safestrncpy(from_host, config.c_fqdn, sizeof from_host);
 468         from_host[sizeof from_host - 1] = 0;
 469         if (num_parms(argbuf)>=5) extract_token(from_host, argbuf, 4, '|', sizeof from_host);
 470
 471         CC->cs_clientdev = dev_code;
 472         CC->cs_clienttyp = cli_code;
 473         CC->cs_clientver = rev_level;
 474         safestrncpy(CC->cs_clientname, desc, sizeof CC->cs_clientname);
 475         CC->cs_clientname[31] = 0;
 476
 477         /* For local sockets and public clients, trust the hostname supplied by the client */
 478         if ( (CC->is_local_socket) || (is_public_client()) ) {
 479                 safestrncpy(CC->cs_host, from_host, sizeof CC->cs_host);
 480                 CC->cs_host[sizeof CC->cs_host - 1] = 0;
 481                 CC->cs_addr[0] = 0;
 482         }
 483
 484         syslog(LOG_NOTICE, "Client %d/%d/%01d.%02d (%s) from %s\n",
 485                 dev_code,
 486                 cli_code,
 487                 (rev_level / 100),
 488                 (rev_level % 100),
 489                 desc,
 490                 CC->cs_host
 491         );
 492         cprintf("%d Ok\n",CIT_OK);
 493 }
 494
 495
 496 /*
 497  * help_subst()  -  support routine for help file viewer
 498  */
 499 void help_subst(char *strbuf, char *source, char *dest)
 500 {
 501         char workbuf[SIZ];
 502         int p;
 503
 504         while (p = pattern2(strbuf, source), (p >= 0)) {
 505                 strcpy(workbuf, &strbuf[p + strlen(source)]);
 506                 strcpy(&strbuf[p], dest);
 507                 strcat(strbuf, workbuf);
 508         }
 509 }
 510
 511 void do_help_subst(char *buffer)
 512 {
 513         char buf2[16];
 514
 515         help_subst(buffer, "^nodename", config.c_nodename);
 516         help_subst(buffer, "^humannode", config.c_humannode);
 517         help_subst(buffer, "^fqdn", config.c_fqdn);
 518         help_subst(buffer, "^username", CC->user.fullname);
 519         snprintf(buf2, sizeof buf2, "%ld", CC->user.usernum);
 520         help_subst(buffer, "^usernum", buf2);
 521         help_subst(buffer, "^sysadm", config.c_sysadm);
 522         help_subst(buffer, "^variantname", CITADEL);
 523         snprintf(buf2, sizeof buf2, "%d", config.c_maxsessions);
 524         help_subst(buffer, "^maxsessions", buf2);
 525         help_subst(buffer, "^bbsdir", ctdl_message_dir);
 526 }
 527
 528
 529 typedef const char *ccharp;
 530 /*
 531  * display system messages or help
 532  */
 533 void cmd_mesg(char *mname)
 534 {
 535         FILE *mfp;
 536         char targ[256];
 537         char buf[256];
 538         char buf2[256];
 539         char *dirs[2];
 540         DIR *dp;
 541         struct dirent *d;
 542
 543         extract_token(buf, mname, 0, '|', sizeof buf);
 544
 545         dirs[0] = strdup(ctdl_message_dir);
 546         dirs[1] = strdup(ctdl_hlp_dir);
 547
 548         snprintf(buf2, sizeof buf2, "%s.%d.%d",
 549                 buf, CC->cs_clientdev, CC->cs_clienttyp);
 550
 551         /* If the client requested "?" then produce a listing */
 552         if (!strcmp(buf, "?")) {
 553                 cprintf("%d %s\n", LISTING_FOLLOWS, buf);
 554                 dp = opendir(dirs[1]);
 555                 if (dp != NULL) {
 556                         while (d = readdir(dp), d != NULL) {
 557                                 if (d->d_name[0] != '.') {
 558                                         cprintf(" %s\n", d->d_name);
 559                                 }
 560                         }
 561                         closedir(dp);
 562                 }
 563                 cprintf("000\n");
 564                 free(dirs[0]);
 565                 free(dirs[1]);
 566                 return;
 567         }
 568
 569         /* Otherwise, look for the requested file by name. */
 570         else {
 571                 mesg_locate(targ, sizeof targ, buf2, 2, (const ccharp*)dirs);
 572                 if (IsEmptyStr(targ)) {
 573                         snprintf(buf2, sizeof buf2, "%s.%d",
 574                                                         buf, CC->cs_clientdev);
 575                         mesg_locate(targ, sizeof targ, buf2, 2,
 576                                     (const ccharp*)dirs);
 577                         if (IsEmptyStr(targ)) {
 578                                 mesg_locate(targ, sizeof targ, buf, 2,
 579                                             (const ccharp*)dirs);
 580                         }
 581                 }
 582         }
 583
 584         free(dirs[0]);
 585         free(dirs[1]);
 586
 587         if (IsEmptyStr(targ)) {
 588                 cprintf("%d '%s' not found.  (Searching in %s and %s)\n",
 589                         ERROR + FILE_NOT_FOUND,
 590                         mname,
 591                         ctdl_message_dir,
 592                         ctdl_hlp_dir
 593                 );
 594                 return;
 595         }
 596
 597         mfp = fopen(targ, "r");
 598         if (mfp==NULL) {
 599                 cprintf("%d Cannot open '%s': %s\n",
 600                         ERROR + INTERNAL_ERROR, targ, strerror(errno));
 601                 return;
 602         }
 603         cprintf("%d %s\n", LISTING_FOLLOWS,buf);
 604
 605         while (fgets(buf, (sizeof buf - 1), mfp) != NULL) {
 606                 buf[strlen(buf)-1] = 0;
 607                 do_help_subst(buf);
 608                 cprintf("%s\n",buf);
 609         }
 610
 611         fclose(mfp);
 612         cprintf("000\n");
 613 }
 614
 615
 616 /*
 617  * enter system messages or help
 618  */
 619 void cmd_emsg(char *mname)
 620 {
 621         FILE *mfp;
 622         char targ[256];
 623         char buf[256];
 624         char *dirs[2];
 625         int a;
 626
 627         unbuffer_output();
 628
 629         if (CtdlAccessCheck(ac_aide)) return;
 630
 631         extract_token(buf, mname, 0, '|', sizeof buf);
 632         for (a=0; !IsEmptyStr(&buf[a]); ++a) {          /* security measure */
 633                 if (buf[a] == '/') buf[a] = '.';
 634         }
 635
 636         dirs[0] = strdup(ctdl_message_dir);
 637         dirs[1] = strdup(ctdl_hlp_dir);
 638
 639         mesg_locate(targ, sizeof targ, buf, 2, (const ccharp*)dirs);
 640         free(dirs[0]);
 641         free(dirs[1]);
 642
 643         if (IsEmptyStr(targ)) {
 644                 snprintf(targ, sizeof targ,
 645                                  "%s/%s",
 646                                  ctdl_hlp_dir, buf);
 647         }
 648
 649         mfp = fopen(targ,"w");
 650         if (mfp==NULL) {
 651                 cprintf("%d Cannot open '%s': %s\n",
 652                         ERROR + INTERNAL_ERROR, targ, strerror(errno));
 653                 return;
 654         }
 655         cprintf("%d %s\n", SEND_LISTING, targ);
 656
 657         while (client_getln(buf, sizeof buf) >=0 && strcmp(buf, "000")) {
 658                 fprintf(mfp, "%s\n", buf);
 659         }
 660
 661         fclose(mfp);
 662 }
 663
 664
 665 /* Don't show the names of private rooms unless the viewing
 666  * user also knows the rooms.
 667  */
 668 void GenerateRoomDisplay(char *real_room,
 669                         CitContext *viewed,
 670                         CitContext *viewer) {
 671
 672         int ra;
 673
 674         strcpy(real_room, viewed->room.QRname);
 675         if (viewed->room.QRflags & QR_MAILBOX) {
 676                 strcpy(real_room, &real_room[11]);
 677         }
 678         if (viewed->room.QRflags & QR_PRIVATE) {
 679                 CtdlRoomAccess(&viewed->room, &viewer->user, &ra, NULL);
 680                 if ( (ra & UA_KNOWN) == 0) {
 681                         strcpy(real_room, " ");
 682                 }
 683         }
 684
 685         if (viewed->cs_flags & CS_CHAT) {
 686                 while (strlen(real_room) < 14) {
 687                         strcat(real_room, " ");
 688                 }
 689                 strcpy(&real_room[14], "<chat>");
 690         }
 691
 692 }
 693
 694 /*
 695  * Convenience function.
 696  */
 697 int CtdlAccessCheck(int required_level) {
 698
 699         if (CC->internal_pgm) return(0);
 700         if (required_level >= ac_internal) {
 701                 cprintf("%d This is not a user-level command.\n",
 702                         ERROR + HIGHER_ACCESS_REQUIRED);
 703                 return(-1);
 704         }
 705
 706         if ((required_level >= ac_logged_in_or_guest) && (CC->logged_in == 0) && (!config.c_guest_logins)) {
 707                 cprintf("%d Not logged in.\n", ERROR + NOT_LOGGED_IN);
 708                 return(-1);
 709         }
 710
 711         if ((required_level >= ac_logged_in) && (CC->logged_in == 0)) {
 712                 cprintf("%d Not logged in.\n", ERROR + NOT_LOGGED_IN);
 713                 return(-1);
 714         }
 715
 716         if (CC->user.axlevel >= AxAideU) return(0);
 717         if (required_level >= ac_aide) {
 718                 cprintf("%d This command requires Admin access.\n",
 719                         ERROR + HIGHER_ACCESS_REQUIRED);
 720                 return(-1);
 721         }
 722
 723         if (is_room_aide()) return(0);
 724         if (required_level >= ac_room_aide) {
 725                 cprintf("%d This command requires Admin or Room Admin access.\n",
 726                         ERROR + HIGHER_ACCESS_REQUIRED);
 727                 return(-1);
 728         }
 729
 730         /* shhh ... succeed quietly */
 731         return(0);
 732 }
 733
 734
 735
 736 /*
 737  * Terminate another running session
 738  */
 739 void cmd_term(char *cmdbuf)
 740 {
 741         int session_num;
 742         int terminated = 0;
 743
 744         session_num = extract_int(cmdbuf, 0);
 745
 746         terminated = CtdlTerminateOtherSession(session_num);
 747
 748         if (terminated < 0) {
 749                 cprintf("%d You can't kill your own session.\n", ERROR + ILLEGAL_VALUE);
 750                 return;
 751         }
 752
 753         if (terminated & TERM_FOUND) {
 754                 if (terminated == TERM_KILLED) {
 755                         cprintf("%d Session terminated.\n", CIT_OK);
 756                 }
 757                 else {
 758                         cprintf("%d You are not allowed to do that.\n",
 759                                 ERROR + HIGHER_ACCESS_REQUIRED);
 760                 }
 761         }
 762         else {
 763                 cprintf("%d No such session.\n", ERROR + ILLEGAL_VALUE);
 764         }
 765 }
 766
 767
 768 /*
 769  * get the paginator prompt
 770  */
 771 void cmd_more(char *argbuf) {
 772         cprintf("%d %s\n", CIT_OK, config.c_moreprompt);
 773 }
 774
 775
 776 /*
 777  * echo
 778  */
 779 void cmd_echo(char *etext)
 780 {
 781         cprintf("%d %s\n", CIT_OK, etext);
 782 }
 783
 784
 785
 786 /*
 787  * Shut down the server
 788  */
 789 void cmd_down(char *argbuf) {
 790         char *Reply ="%d Shutting down server.  Goodbye.\n";
 791
 792         if (CtdlAccessCheck(ac_aide)) return;
 793
 794         if (!IsEmptyStr(argbuf))
 795         {
 796                 int state = CIT_OK;
 797                 restart_server = extract_int(argbuf, 0);
 798
 799                 if (restart_server > 0)
 800                 {
 801                         Reply = "%d citserver will now shut down and automatically restart.\n";
 802                 }
 803                 if ((restart_server > 0) && !running_as_daemon)
 804                 {
 805                         syslog(LOG_ERR, "The user requested restart, but not running as daemon! Geronimooooooo!\n");
 806                         Reply = "%d Warning: citserver is not running in daemon mode and is therefore unlikely to restart automatically.\n";
 807                         state = ERROR;
 808                 }
 809                 cprintf(Reply, state);
 810         }
 811         else
 812         {
 813                 cprintf(Reply, CIT_OK + SERVER_SHUTTING_DOWN);
 814         }
 815         CC->kill_me = KILLME_SERVER_SHUTTING_DOWN;
 816         server_shutting_down = 1;
 817 }
 818
 819
 820 /*
 821  * Halt the server without exiting the server process.
 822  */
 823 void cmd_halt(char *argbuf) {
 824
 825         if (CtdlAccessCheck(ac_aide)) return;
 826
 827         cprintf("%d Halting server.  Goodbye.\n", CIT_OK);
 828         server_shutting_down = 1;
 829         shutdown_and_halt = 1;
 830 }
 831
 832
 833 /*
 834  * Schedule or cancel a server shutdown
 835  */
 836 void cmd_scdn(char *argbuf)
 837 {
 838         int new_state;
 839         int state = CIT_OK;
 840         char *Reply = "%d %d\n";
 841
 842         if (CtdlAccessCheck(ac_aide)) return;
 843
 844         new_state = extract_int(argbuf, 0);
 845         if ((new_state == 2) || (new_state == 3))
 846         {
 847                 restart_server = 1;
 848                 if (!running_as_daemon)
 849                 {
 850                         syslog(LOG_ERR, "The user requested restart, but not running as deamon! Geronimooooooo!\n");
 851                         Reply = "%d %d Warning, not running in deamon mode. maybe we will come up again, but don't lean on it.\n";
 852                         state = ERROR;
 853                 }
 854
 855                 restart_server = extract_int(argbuf, 0);
 856                 new_state -= 2;
 857         }
 858         if ((new_state == 0) || (new_state == 1)) {
 859                 ScheduledShutdown = new_state;
 860         }
 861         cprintf(Reply, state, ScheduledShutdown);
 862 }
 863
 864
 865 /*
 866  * Set or unset asynchronous protocol mode
 867  */
 868 void cmd_asyn(char *argbuf)
 869 {
 870         int new_state;
 871
 872         new_state = extract_int(argbuf, 0);
 873         if ((new_state == 0) || (new_state == 1)) {
 874                 CC->is_async = new_state;
 875         }
 876         cprintf("%d %d\n", CIT_OK, CC->is_async);
 877 }
 878
 879
 880
 881 /*
 882  * Back-end function for starting a session
 883  */
 884 void begin_session(CitContext *con)
 885 {
 886         /*
 887          * Initialize some variables specific to our context.
 888          */
 889         con->logged_in = 0;
 890         con->internal_pgm = 0;
 891         con->download_fp = NULL;
 892         con->upload_fp = NULL;
 893         con->cached_msglist = NULL;
 894         con->cached_num_msgs = 0;
 895         con->FirstExpressMessage = NULL;
 896         time(&con->lastcmd);
 897         time(&con->lastidle);
 898         strcpy(con->lastcmdname, "    ");
 899         strcpy(con->cs_clientname, "(unknown)");
 900         strcpy(con->curr_user, NLI);
 901         *con->net_node = '\0';
 902         *con->fake_username = '\0';
 903         *con->fake_hostname = '\0';
 904         *con->fake_roomname = '\0';
 905         *con->cs_clientinfo = '\0';
 906         safestrncpy(con->cs_host, config.c_fqdn, sizeof con->cs_host);
 907         safestrncpy(con->cs_addr, "", sizeof con->cs_addr);
 908         con->cs_UDSclientUID = -1;
 909         con->cs_host[sizeof con->cs_host - 1] = 0;
 910         if (!CC->is_local_socket) {
 911                 locate_host(con->cs_host, sizeof con->cs_host,
 912                         con->cs_addr, sizeof con->cs_addr,
 913                         con->client_socket
 914                 );
 915         }
 916         else {
 917                 con->cs_host[0] = 0;
 918                 con->cs_addr[0] = 0;
 919 #ifdef HAVE_STRUCT_UCRED
 920                 {
 921                         /* as http://www.wsinnovations.com/softeng/articles/uds.html told us... */
 922                         struct ucred credentials;
 923                         socklen_t ucred_length = sizeof(struct ucred);
 924
 925                         /*fill in the user data structure */
 926                         if(getsockopt(con->client_socket, SOL_SOCKET, SO_PEERCRED, &credentials, &ucred_length)) {
 927                                 syslog(LOG_NOTICE, "could obtain credentials from unix domain socket");
 928
 929                         }
 930                         else {
 931                                 /* the process ID of the process on the other side of the socket */
 932                                 /* credentials.pid; */
 933
 934                                 /* the effective UID of the process on the other side of the socket  */
 935                                 con->cs_UDSclientUID = credentials.uid;
 936
 937                                 /* the effective primary GID of the process on the other side of the socket */
 938                                 /* credentials.gid; */
 939
 940                                 /* To get supplemental groups, we will have to look them up in our account
 941                                    database, after a reverse lookup on the UID to get the account name.
 942                                    We can take this opportunity to check to see if this is a legit account.
 943                                 */
 944                                 snprintf(con->cs_clientinfo, sizeof(con->cs_clientinfo),
 945                                          "PID: "F_PID_T"; UID: "F_UID_T"; GID: "F_XPID_T" ",
 946                                          credentials.pid,
 947                                          credentials.uid,
 948                                          credentials.gid);
 949                         }
 950                 }
 951 #endif
 952         }
 953         con->cs_flags = 0;
 954         con->upload_type = UPL_FILE;
 955         con->dl_is_net = 0;
 956
 957         con->nologin = 0;
 958         if (((config.c_maxsessions > 0)&&(num_sessions > config.c_maxsessions)) || CtdlWantSingleUser()) {
 959                 con->nologin = 1;
 960         }
 961
 962         if (!CC->is_local_socket) {
 963                 syslog(LOG_NOTICE, "Session (%s) started from %s (%s).\n", con->ServiceName, con->cs_host, con->cs_addr);
 964         }
 965         else {
 966                 syslog(LOG_NOTICE, "Session (%s) started via local socket UID:%d.\n", con->ServiceName, con->cs_UDSclientUID);
 967         }
 968
 969         /* Run any session startup routines registered by loadable modules */
 970         PerformSessionHooks(EVT_START);
 971 }
 972
 973
 974 void citproto_begin_session() {
 975         if (CC->nologin==1) {
 976                 cprintf("%d %s: Too many users are already online (maximum is %d)\n",
 977                         ERROR + MAX_SESSIONS_EXCEEDED,
 978                         config.c_nodename, config.c_maxsessions
 979                 );
 980                 CC->kill_me = KILLME_MAX_SESSIONS_EXCEEDED;
 981         }
 982         else {
 983                 cprintf("%d %s Citadel server ready.\n", CIT_OK, config.c_nodename);
 984                 CC->can_receive_im = 1;
 985         }
 986 }
 987
 988
 989 void citproto_begin_admin_session() {
 990         CC->internal_pgm = 1;
 991         cprintf("%d %s Citadel server ADMIN CONNECTION ready.\n", CIT_OK, config.c_nodename);
 992 }
 993
 994
 995 void cmd_noop(char *argbuf)
 996 {
 997         cprintf("%d%cok\n", CIT_OK, CtdlCheckExpress() );
 998 }
 999
1000
1001 void cmd_qnop(char *argbuf)
1002 {
1003         /* do nothing, this command returns no response */
1004 }
1005
1006
1007 void cmd_quit(char *argbuf)
1008 {
1009         cprintf("%d Goodbye.\n", CIT_OK);
1010         CC->kill_me = KILLME_CLIENT_LOGGED_OUT;
1011 }
1012
1013
1014 void cmd_lout(char *argbuf)
1015 {
1016         if (CC->logged_in)
1017                 CtdlUserLogout();
1018         cprintf("%d logged out.\n", CIT_OK);
1019 }
1020
1021
1022 /*
1023  * This loop recognizes all server commands.
1024  */
1025 void do_command_loop(void) {
1026         char cmdbuf[SIZ];
1027
1028         time(&CC->lastcmd);
1029         memset(cmdbuf, 0, sizeof cmdbuf); /* Clear it, just in case */
1030         if (client_getln(cmdbuf, sizeof cmdbuf) < 1) {
1031                 syslog(LOG_ERR, "Citadel client disconnected: ending session.\n");
1032                 CC->kill_me = KILLME_CLIENT_DISCONNECTED;
1033                 return;
1034         }
1035
1036         /* Log the server command, but don't show passwords... */
1037         if ( (strncasecmp(cmdbuf, "PASS", 4)) && (strncasecmp(cmdbuf, "SETP", 4)) ) {
1038                 syslog(LOG_INFO, "[%d][%s(%ld)] %s",
1039                         CC->cs_pid, CC->curr_user, CC->user.usernum, cmdbuf
1040                 );
1041         }
1042         else {
1043                 syslog(LOG_INFO, "[%d][%s(%ld)] <password command hidden from log>",
1044                         CC->cs_pid, CC->curr_user, CC->user.usernum
1045                 );
1046         }
1047
1048         buffer_output();
1049
1050         /*
1051          * Let other clients see the last command we executed, and
1052          * update the idle time, but not NOOP, QNOP, PEXP, GEXP, RWHO, or TIME.
1053          */
1054         if ( (strncasecmp(cmdbuf, "NOOP", 4))
1055            && (strncasecmp(cmdbuf, "QNOP", 4))
1056            && (strncasecmp(cmdbuf, "PEXP", 4))
1057            && (strncasecmp(cmdbuf, "GEXP", 4))
1058            && (strncasecmp(cmdbuf, "RWHO", 4))
1059            && (strncasecmp(cmdbuf, "TIME", 4)) ) {
1060                 strcpy(CC->lastcmdname, "    ");
1061                 safestrncpy(CC->lastcmdname, cmdbuf, sizeof(CC->lastcmdname));
1062                 time(&CC->lastidle);
1063         }
1064
1065         if ((strncasecmp(cmdbuf, "ENT0", 4))
1066            && (strncasecmp(cmdbuf, "MESG", 4))
1067            && (strncasecmp(cmdbuf, "MSGS", 4)))
1068         {
1069            CC->cs_flags &= ~CS_POSTING;
1070         }
1071
1072         if (!DLoader_Exec_Cmd(cmdbuf)) {
1073                 cprintf("%d Unrecognized or unsupported command.\n", ERROR + CMD_NOT_SUPPORTED);
1074         }
1075
1076         unbuffer_output();
1077
1078         /* Run any after-each-command routines registered by modules */
1079         PerformSessionHooks(EVT_CMD);
1080 }
1081
1082
1083 /*
1084  * This loop performs all asynchronous functions.
1085  */
1086 void do_async_loop(void) {
1087         PerformSessionHooks(EVT_ASYNC);
1088 }
1089
1090
1091 /*****************************************************************************/
1092 /*                      MODULE INITIALIZATION STUFF                          */
1093 /*****************************************************************************/
1094
1095 CTDL_MODULE_INIT(citserver)
1096 {
1097         if (!threading) {
1098                 CtdlRegisterProtoHook(cmd_noop, "NOOP", "no operation");
1099                 CtdlRegisterProtoHook(cmd_qnop, "QNOP", "no operation with no response");
1100                 CtdlRegisterProtoHook(cmd_quit, "QUIT", "log out and disconnect from server");
1101                 CtdlRegisterProtoHook(cmd_lout, "LOUT", "log out but do not disconnect from server");
1102                 CtdlRegisterProtoHook(cmd_asyn, "ASYN", "enable asynchronous server responses");
1103                 CtdlRegisterProtoHook(cmd_info, "INFO", "fetch server capabilities and configuration");
1104                 CtdlRegisterProtoHook(cmd_mesg, "MESG", "fetch system banners");
1105                 CtdlRegisterProtoHook(cmd_emsg, "EMSG", "submit system banners");
1106                 CtdlRegisterProtoHook(cmd_echo, "ECHO", "echo text back to the client");
1107                 CtdlRegisterProtoHook(cmd_more, "MORE", "fetch the paginator prompt");
1108                 CtdlRegisterProtoHook(cmd_iden, "IDEN", "identify the client software and location");
1109                 CtdlRegisterProtoHook(cmd_term, "TERM", "terminate another running session");
1110                 CtdlRegisterProtoHook(cmd_down, "DOWN", "perform a server shutdown");
1111                 CtdlRegisterProtoHook(cmd_halt, "HALT", "halt the server without exiting the server process");
1112                 CtdlRegisterProtoHook(cmd_scdn, "SCDN", "schedule or cancel a server shutdown");
1113                 CtdlRegisterProtoHook(cmd_time, "TIME", "fetch the date and time from the server");
1114         }
1115         /* return our id for the Log */
1116         return "citserver";
1117 }