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
  69 #ifndef HAVE_SNPRINTF
  70 #include "snprintf.h"
  71 #endif
  72
  73 #include "ctdl_module.h"
  74
  75 char *unique_session_numbers;
  76 int ScheduledShutdown = 0;
  77 time_t server_startup_time;
  78 int panic_fd;
  79 int openid_level_supported = 0;
  80
  81 /*
  82  * print the actual stack frame.
  83  */
  84 void cit_backtrace(void)
  85 {
  86 #ifdef HAVE_BACKTRACE
  87         void *stack_frames[50];
  88         size_t size, i;
  89         char **strings;
  90
  91
  92         size = backtrace(stack_frames, sizeof(stack_frames) / sizeof(void*));
  93         strings = backtrace_symbols(stack_frames, size);
  94         for (i = 0; i < size; i++) {
  95                 if (strings != NULL)
  96                         syslog(LOG_ALERT, "%s\n", strings[i]);
  97                 else
  98                         syslog(LOG_ALERT, "%p\n", stack_frames[i]);
  99         }
 100         free(strings);
 101 #endif
 102 }
 103
 104 void cit_oneline_backtrace(void)
 105 {
 106 #ifdef HAVE_BACKTRACE
 107         void *stack_frames[50];
 108         size_t size, i;
 109         char **strings;
 110         StrBuf *Buf;
 111
 112         size = backtrace(stack_frames, sizeof(stack_frames) / sizeof(void*));
 113         strings = backtrace_symbols(stack_frames, size);
 114         if (size > 0)
 115         {
 116                 Buf = NewStrBuf();
 117                 for (i = 1; i < size; i++) {
 118                         if (strings != NULL)
 119                                 StrBufAppendPrintf(Buf, "%s : ", strings[i]);
 120                         else
 121                                 StrBufAppendPrintf(Buf, "%p : ", stack_frames[i]);
 122                 }
 123                 free(strings);
 124                 syslog(LOG_ALERT, "%s\n", ChrPtr(Buf));
 125                 FreeStrBuf(&Buf);
 126         }
 127 #endif
 128 }
 129
 130 /*
 131  * print the actual stack frame.
 132  */
 133 void cit_panic_backtrace(int SigNum)
 134 {
 135 #ifdef HAVE_BACKTRACE
 136         void *stack_frames[10];
 137         size_t size, i;
 138         char **strings;
 139
 140         printf("caught signal 11\n");
 141         size = backtrace(stack_frames, sizeof(stack_frames) / sizeof(void*));
 142         strings = backtrace_symbols(stack_frames, size);
 143         for (i = 0; i < size; i++) {
 144                 if (strings != NULL)
 145                         syslog(LOG_ALERT, "%s\n", strings[i]);
 146                 else
 147                         syslog(LOG_ALERT, "%p\n", stack_frames[i]);
 148         }
 149         free(strings);
 150 #endif
 151         exit(-1);
 152 }
 153
 154 /*
 155  * Various things that need to be initialized at startup
 156  */
 157 void master_startup(void) {
 158         struct timeval tv;
 159         unsigned int seed;
 160         FILE *urandom;
 161         struct ctdlroom qrbuf;
 162         int rv;
 163
 164         syslog(LOG_DEBUG, "master_startup() started\n");
 165         time(&server_startup_time);
 166         get_config();
 167
 168         syslog(LOG_INFO, "Opening databases\n");
 169         open_databases();
 170         check_ref_counts();
 171
 172         syslog(LOG_INFO, "Creating base rooms (if necessary)\n");
 173         CtdlCreateRoom(config.c_baseroom,       0, "", 0, 1, 0, VIEW_BBS);
 174         CtdlCreateRoom(AIDEROOM,                3, "", 0, 1, 0, VIEW_BBS);
 175         CtdlCreateRoom(SYSCONFIGROOM,           3, "", 0, 1, 0, VIEW_BBS);
 176         CtdlCreateRoom(config.c_twitroom,       0, "", 0, 1, 0, VIEW_BBS);
 177
 178         /* The "Local System Configuration" room doesn't need to be visible */
 179         if (CtdlGetRoomLock(&qrbuf, SYSCONFIGROOM) == 0) {
 180                 qrbuf.QRflags2 |= QR2_SYSTEM;
 181                 CtdlPutRoomLock(&qrbuf);
 182         }
 183
 184         /* Aide needs to be public postable, else we're not RFC conformant. */
 185         if (CtdlGetRoomLock(&qrbuf, AIDEROOM) == 0) {
 186                 qrbuf.QRflags2 |= QR2_SMTP_PUBLIC;
 187                 CtdlPutRoomLock(&qrbuf);
 188         }
 189
 190         syslog(LOG_INFO, "Seeding the pseudo-random number generator...\n");
 191         urandom = fopen("/dev/urandom", "r");
 192         if (urandom != NULL) {
 193                 rv = fread(&seed, sizeof seed, 1, urandom);
 194                 if (rv == -1)
 195                         syslog(LOG_EMERG, "failed to read random seed: %s\n",
 196                                strerror(errno));
 197                 fclose(urandom);
 198         }
 199         else {
 200                 gettimeofday(&tv, NULL);
 201                 seed = tv.tv_usec;
 202         }
 203         srand(seed);
 204         srandom(seed);
 205
 206         put_config();
 207
 208         syslog(LOG_DEBUG, "master_startup() finished\n");
 209 }
 210
 211
 212 /*
 213  * Cleanup routine to be called when the server is shutting down.
 214  */
 215 void master_cleanup(int exitcode) {
 216         struct CleanupFunctionHook *fcn;
 217         static int already_cleaning_up = 0;
 218
 219         if (already_cleaning_up) while(1) usleep(1000000);
 220         already_cleaning_up = 1;
 221
 222         /* Run any cleanup routines registered by loadable modules */
 223         for (fcn = CleanupHookTable; fcn != NULL; fcn = fcn->next) {
 224                 (*fcn->h_function_pointer)();
 225         }
 226
 227         /* Close the AdjRefCount queue file */
 228         AdjRefCount(-1, 0);
 229
 230         /* Do system-dependent stuff */
 231         sysdep_master_cleanup();
 232
 233         /* Close databases */
 234         syslog(LOG_INFO, "Closing databases\n");
 235         close_databases();
 236
 237         /* If the operator requested a halt but not an exit, halt here. */
 238         if (shutdown_and_halt) {
 239                 syslog(LOG_NOTICE, "citserver: Halting server without exiting.\n");
 240                 fflush(stdout); fflush(stderr);
 241                 while(1) {
 242                         sleep(32767);
 243                 }
 244         }
 245
 246         release_control();
 247
 248         /* Now go away. */
 249         syslog(LOG_NOTICE, "citserver: Exiting with status %d\n", exitcode);
 250         fflush(stdout); fflush(stderr);
 251
 252         if (restart_server != 0)
 253                 exit(1);
 254         if ((running_as_daemon != 0) && ((exitcode == 0) ))
 255                 exitcode = CTDLEXIT_SHUTDOWN;
 256         exit(exitcode);
 257 }
 258
 259
 260
 261 /*
 262  * cmd_info()  -  tell the client about this server
 263  */
 264 void cmd_info(char *cmdbuf) {
 265         cprintf("%d Server info:\n", LISTING_FOLLOWS);
 266         cprintf("%d\n", CC->cs_pid);
 267         cprintf("%s\n", config.c_nodename);
 268         cprintf("%s\n", config.c_humannode);
 269         cprintf("%s\n", config.c_fqdn);
 270         cprintf("%s\n", CITADEL);
 271         cprintf("%d\n", REV_LEVEL);
 272         cprintf("%s\n", config.c_site_location);
 273         cprintf("%s\n", config.c_sysadm);
 274         cprintf("%d\n", SERVER_TYPE);
 275         cprintf("%s\n", config.c_moreprompt);
 276         cprintf("1\n"); /* 1 = yes, this system supports floors */
 277         cprintf("1\n"); /* 1 = we support the extended paging options */
 278         cprintf("\n");  /* nonce no longer supported */
 279         cprintf("1\n"); /* 1 = yes, this system supports the QNOP command */
 280
 281 #ifdef HAVE_LDAP
 282         cprintf("1\n"); /* 1 = yes, this server is LDAP-enabled */
 283 #else
 284         cprintf("0\n"); /* 1 = no, this server is not LDAP-enabled */
 285 #endif
 286
 287         if (config.c_auth_mode == AUTHMODE_NATIVE) {
 288                 cprintf("%d\n", config.c_disable_newu);
 289         }
 290         else {
 291                 cprintf("1\n"); /* "create new user" does not work with non-native auth modes */
 292         }
 293
 294         cprintf("%s\n", config.c_default_cal_zone);
 295
 296         /* thread load averages -- temporarily disabled during refactoring of this code */
 297         cprintf("0\n");         /* load average */
 298         cprintf("0\n");         /* worker average */
 299         cprintf("0\n");         /* thread count */
 300
 301         cprintf("1\n");         /* yes, Sieve mail filtering is supported */
 302         cprintf("%d\n", config.c_enable_fulltext);
 303         cprintf("%s\n", svn_revision());
 304
 305         if (config.c_auth_mode == AUTHMODE_NATIVE) {
 306                 cprintf("%d\n", openid_level_supported); /* OpenID is enabled when using native auth */
 307         }
 308         else {
 309                 cprintf("0\n"); /* OpenID is disabled when using non-native auth */
 310         }
 311
 312         cprintf("%d\n", config.c_guest_logins);
 313
 314         cprintf("000\n");
 315 }
 316
 317
 318 /*
 319  * returns an asterisk if there are any instant messages waiting,
 320  * space otherwise.
 321  */
 322 char CtdlCheckExpress(void) {
 323         if (CC->FirstExpressMessage == NULL) {
 324                 return(' ');
 325         }
 326         else {
 327                 return('*');
 328         }
 329 }
 330
 331 void cmd_time(char *argbuf)
 332 {
 333    time_t tv;
 334    struct tm tmp;
 335
 336    tv = time(NULL);
 337    localtime_r(&tv, &tmp);
 338
 339    /* timezone and daylight global variables are not portable. */
 340 #ifdef HAVE_STRUCT_TM_TM_GMTOFF
 341    cprintf("%d %ld|%ld|%d|%ld\n", CIT_OK, (long)tv, tmp.tm_gmtoff, tmp.tm_isdst, server_startup_time);
 342 #else
 343    cprintf("%d %ld|%ld|%d|%ld\n", CIT_OK, (long)tv, timezone, tmp.tm_isdst, server_startup_time);
 344 #endif
 345 }
 346
 347
 348 /*
 349  * Check originating host against the public_clients file.  This determines
 350  * whether the client is allowed to change the hostname for this session
 351  * (for example, to show the location of the user rather than the location
 352  * of the client).
 353  */
 354 int is_public_client(void)
 355 {
 356         char buf[1024];
 357         char addrbuf[1024];
 358         FILE *fp;
 359         int i;
 360         char *public_clientspos;
 361         char *public_clientsend;
 362         char *paddr = NULL;
 363         struct stat statbuf;
 364         static time_t pc_timestamp = 0;
 365         static char public_clients[SIZ];
 366         static char public_clients_file[SIZ];
 367
 368 #define LOCALHOSTSTR "127.0.0.1"
 369
 370         snprintf(public_clients_file, sizeof public_clients_file, "%s/public_clients", ctdl_etc_dir);
 371
 372         /*
 373          * Check the time stamp on the public_clients file.  If it's been
 374          * updated since the last time we were here (or if this is the first
 375          * time we've been through the loop), read its contents and learn
 376          * the IP addresses of the listed hosts.
 377          */
 378         if (stat(public_clients_file, &statbuf) != 0) {
 379                 /* No public_clients file exists, so bail out */
 380                 syslog(LOG_WARNING, "Warning: '%s' does not exist\n",
 381                                 public_clients_file);
 382                 return(0);
 383         }
 384
 385         if (statbuf.st_mtime > pc_timestamp) {
 386                 begin_critical_section(S_PUBLIC_CLIENTS);
 387                 syslog(LOG_INFO, "Loading %s\n", public_clients_file);
 388
 389                 public_clientspos = &public_clients[0];
 390                 public_clientsend = public_clientspos + SIZ;
 391                 safestrncpy(public_clientspos, LOCALHOSTSTR, sizeof public_clients);
 392                 public_clientspos += sizeof(LOCALHOSTSTR) - 1;
 393
 394                 if (hostname_to_dotted_quad(addrbuf, config.c_fqdn) == 0) {
 395                         *(public_clientspos++) = '|';
 396                         paddr = &addrbuf[0];
 397                         while (!IsEmptyStr (paddr) &&
 398                                (public_clientspos < public_clientsend))
 399                                 *(public_clientspos++) = *(paddr++);
 400                 }
 401
 402                 fp = fopen(public_clients_file, "r");
 403                 if (fp != NULL)
 404                         while ((fgets(buf, sizeof buf, fp)!=NULL) &&
 405                                (public_clientspos < public_clientsend)){
 406                                 char *ptr;
 407                                 ptr = buf;
 408                                 while (!IsEmptyStr(ptr)) {
 409                                         if (*ptr == '#') {
 410                                                 *ptr = 0;
 411                                                 break;
 412                                         }
 413                                 else ptr++;
 414                                 }
 415                                 ptr--;
 416                                 while (ptr>buf && isspace(*ptr)) {
 417                                         *(ptr--) = 0;
 418                                 }
 419                                 if (hostname_to_dotted_quad(addrbuf, buf) == 0) {
 420                                         *(public_clientspos++) = '|';
 421                                         paddr = addrbuf;
 422                                         while (!IsEmptyStr(paddr) &&
 423                                                (public_clientspos < public_clientsend)){
 424                                                 *(public_clientspos++) = *(paddr++);
 425                                         }
 426                                 }
 427                         }
 428                 if (fp != NULL) fclose(fp);
 429                 pc_timestamp = time(NULL);
 430                 end_critical_section(S_PUBLIC_CLIENTS);
 431         }
 432
 433         syslog(LOG_DEBUG, "Checking whether %s is a local or public client\n",
 434                 CC->cs_addr);
 435         for (i=0; i<num_parms(public_clients); ++i) {
 436                 extract_token(addrbuf, public_clients, i, '|', sizeof addrbuf);
 437                 if (!strcasecmp(CC->cs_addr, addrbuf)) {
 438                         syslog(LOG_DEBUG, "... yes its local.\n");
 439                         return(1);
 440                 }
 441         }
 442
 443         /* No hits.  This is not a public client. */
 444         syslog(LOG_DEBUG, "... no it isn't.\n");
 445         return(0);
 446 }
 447
 448
 449 /*
 450  * the client is identifying itself to the server
 451  */
 452 void cmd_iden(char *argbuf)
 453 {
 454         int dev_code;
 455         int cli_code;
 456         int rev_level;
 457         char desc[128];
 458         char from_host[128];
 459
 460         if (num_parms(argbuf)<4) {
 461                 cprintf("%d usage error\n", ERROR + ILLEGAL_VALUE);
 462                 return;
 463         }
 464
 465         dev_code = extract_int(argbuf,0);
 466         cli_code = extract_int(argbuf,1);
 467         rev_level = extract_int(argbuf,2);
 468         extract_token(desc, argbuf, 3, '|', sizeof desc);
 469
 470         safestrncpy(from_host, config.c_fqdn, sizeof from_host);
 471         from_host[sizeof from_host - 1] = 0;
 472         if (num_parms(argbuf)>=5) extract_token(from_host, argbuf, 4, '|', sizeof from_host);
 473
 474         CC->cs_clientdev = dev_code;
 475         CC->cs_clienttyp = cli_code;
 476         CC->cs_clientver = rev_level;
 477         safestrncpy(CC->cs_clientname, desc, sizeof CC->cs_clientname);
 478         CC->cs_clientname[31] = 0;
 479
 480         /* For local sockets and public clients, trust the hostname supplied by the client */
 481         if ( (CC->is_local_socket) || (is_public_client()) ) {
 482                 safestrncpy(CC->cs_host, from_host, sizeof CC->cs_host);
 483                 CC->cs_host[sizeof CC->cs_host - 1] = 0;
 484                 CC->cs_addr[0] = 0;
 485         }
 486
 487         syslog(LOG_NOTICE, "Client %d/%d/%01d.%02d (%s) from %s\n",
 488                 dev_code,
 489                 cli_code,
 490                 (rev_level / 100),
 491                 (rev_level % 100),
 492                 desc,
 493                 CC->cs_host
 494         );
 495         cprintf("%d Ok\n",CIT_OK);
 496 }
 497
 498 typedef const char *ccharp;
 499 /*
 500  * display system messages or help
 501  */
 502 void cmd_mesg(char *mname)
 503 {
 504         FILE *mfp;
 505         char targ[256];
 506         char buf[256];
 507         char buf2[256];
 508         char *dirs[2];
 509         DIR *dp;
 510         struct dirent *d;
 511
 512         extract_token(buf, mname, 0, '|', sizeof buf);
 513
 514         dirs[0] = strdup(ctdl_message_dir);
 515         dirs[1] = strdup(ctdl_hlp_dir);
 516
 517         snprintf(buf2, sizeof buf2, "%s.%d.%d",
 518                 buf, CC->cs_clientdev, CC->cs_clienttyp);
 519
 520         /* If the client requested "?" then produce a listing */
 521         if (!strcmp(buf, "?")) {
 522                 cprintf("%d %s\n", LISTING_FOLLOWS, buf);
 523                 dp = opendir(dirs[1]);
 524                 if (dp != NULL) {
 525                         while (d = readdir(dp), d != NULL) {
 526                                 if (d->d_name[0] != '.') {
 527                                         cprintf(" %s\n", d->d_name);
 528                                 }
 529                         }
 530                         closedir(dp);
 531                 }
 532                 cprintf("000\n");
 533                 free(dirs[0]);
 534                 free(dirs[1]);
 535                 return;
 536         }
 537
 538         /* Otherwise, look for the requested file by name. */
 539         else {
 540                 mesg_locate(targ, sizeof targ, buf2, 2, (const ccharp*)dirs);
 541                 if (IsEmptyStr(targ)) {
 542                         snprintf(buf2, sizeof buf2, "%s.%d",
 543                                                         buf, CC->cs_clientdev);
 544                         mesg_locate(targ, sizeof targ, buf2, 2,
 545                                     (const ccharp*)dirs);
 546                         if (IsEmptyStr(targ)) {
 547                                 mesg_locate(targ, sizeof targ, buf, 2,
 548                                             (const ccharp*)dirs);
 549                         }
 550                 }
 551         }
 552
 553         free(dirs[0]);
 554         free(dirs[1]);
 555
 556         if (IsEmptyStr(targ)) {
 557                 cprintf("%d '%s' not found.  (Searching in %s and %s)\n",
 558                         ERROR + FILE_NOT_FOUND,
 559                         mname,
 560                         ctdl_message_dir,
 561                         ctdl_hlp_dir
 562                 );
 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, (sizeof buf - 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[256];
 592         char buf[256];
 593         char *dirs[2];
 594         int a;
 595
 596         unbuffer_output();
 597
 598         if (CtdlAccessCheck(ac_aide)) return;
 599
 600         extract_token(buf, mname, 0, '|', sizeof buf);
 601         for (a=0; !IsEmptyStr(&buf[a]); ++a) {          /* security measure */
 602                 if (buf[a] == '/') buf[a] = '.';
 603         }
 604
 605         dirs[0] = strdup(ctdl_message_dir);
 606         dirs[1] = strdup(ctdl_hlp_dir);
 607
 608         mesg_locate(targ, sizeof targ, buf, 2, (const ccharp*)dirs);
 609         free(dirs[0]);
 610         free(dirs[1]);
 611
 612         if (IsEmptyStr(targ)) {
 613                 snprintf(targ, sizeof targ,
 614                                  "%s/%s",
 615                                  ctdl_hlp_dir, buf);
 616         }
 617
 618         mfp = fopen(targ,"w");
 619         if (mfp==NULL) {
 620                 cprintf("%d Cannot open '%s': %s\n",
 621                         ERROR + INTERNAL_ERROR, targ, strerror(errno));
 622                 return;
 623         }
 624         cprintf("%d %s\n", SEND_LISTING, targ);
 625
 626         while (client_getln(buf, sizeof buf) >=0 && strcmp(buf, "000")) {
 627                 fprintf(mfp, "%s\n", buf);
 628         }
 629
 630         fclose(mfp);
 631 }
 632
 633
 634 /* Don't show the names of private rooms unless the viewing
 635  * user also knows the rooms.
 636  */
 637 void GenerateRoomDisplay(char *real_room,
 638                         CitContext *viewed,
 639                         CitContext *viewer) {
 640
 641         int ra;
 642
 643         strcpy(real_room, viewed->room.QRname);
 644         if (viewed->room.QRflags & QR_MAILBOX) {
 645                 strcpy(real_room, &real_room[11]);
 646         }
 647         if (viewed->room.QRflags & QR_PRIVATE) {
 648                 CtdlRoomAccess(&viewed->room, &viewer->user, &ra, NULL);
 649                 if ( (ra & UA_KNOWN) == 0) {
 650                         strcpy(real_room, " ");
 651                 }
 652         }
 653
 654         if (viewed->cs_flags & CS_CHAT) {
 655                 while (strlen(real_room) < 14) {
 656                         strcat(real_room, " ");
 657                 }
 658                 strcpy(&real_room[14], "<chat>");
 659         }
 660
 661 }
 662
 663 /*
 664  * Convenience function.
 665  */
 666 int CtdlAccessCheck(int required_level) {
 667
 668         if (CC->internal_pgm) return(0);
 669         if (required_level >= ac_internal) {
 670                 cprintf("%d This is not a user-level command.\n",
 671                         ERROR + HIGHER_ACCESS_REQUIRED);
 672                 return(-1);
 673         }
 674
 675         if ((required_level >= ac_logged_in_or_guest) && (CC->logged_in == 0) && (!config.c_guest_logins)) {
 676                 cprintf("%d Not logged in.\n", ERROR + NOT_LOGGED_IN);
 677                 return(-1);
 678         }
 679
 680         if ((required_level >= ac_logged_in) && (CC->logged_in == 0)) {
 681                 cprintf("%d Not logged in.\n", ERROR + NOT_LOGGED_IN);
 682                 return(-1);
 683         }
 684
 685         if (CC->user.axlevel >= AxAideU) return(0);
 686         if (required_level >= ac_aide) {
 687                 cprintf("%d This command requires Admin access.\n",
 688                         ERROR + HIGHER_ACCESS_REQUIRED);
 689                 return(-1);
 690         }
 691
 692         if (is_room_aide()) return(0);
 693         if (required_level >= ac_room_aide) {
 694                 cprintf("%d This command requires Admin or Room Admin access.\n",
 695                         ERROR + HIGHER_ACCESS_REQUIRED);
 696                 return(-1);
 697         }
 698
 699         /* shhh ... succeed quietly */
 700         return(0);
 701 }
 702
 703
 704
 705 /*
 706  * Terminate another running session
 707  */
 708 void cmd_term(char *cmdbuf)
 709 {
 710         int session_num;
 711         int terminated = 0;
 712
 713         session_num = extract_int(cmdbuf, 0);
 714
 715         terminated = CtdlTerminateOtherSession(session_num);
 716
 717         if (terminated < 0) {
 718                 cprintf("%d You can't kill your own session.\n", ERROR + ILLEGAL_VALUE);
 719                 return;
 720         }
 721
 722         if (terminated & TERM_FOUND) {
 723                 if (terminated == TERM_KILLED) {
 724                         cprintf("%d Session terminated.\n", CIT_OK);
 725                 }
 726                 else {
 727                         cprintf("%d You are not allowed to do that.\n",
 728                                 ERROR + HIGHER_ACCESS_REQUIRED);
 729                 }
 730         }
 731         else {
 732                 cprintf("%d No such session.\n", ERROR + ILLEGAL_VALUE);
 733         }
 734 }
 735
 736
 737 /*
 738  * get the paginator prompt
 739  */
 740 void cmd_more(char *argbuf) {
 741         cprintf("%d %s\n", CIT_OK, config.c_moreprompt);
 742 }
 743
 744
 745 /*
 746  * echo
 747  */
 748 void cmd_echo(char *etext)
 749 {
 750         cprintf("%d %s\n", CIT_OK, etext);
 751 }
 752
 753
 754
 755 /*
 756  * Shut down the server
 757  */
 758 void cmd_down(char *argbuf) {
 759         char *Reply ="%d Shutting down server.  Goodbye.\n";
 760
 761         if (CtdlAccessCheck(ac_aide)) return;
 762
 763         if (!IsEmptyStr(argbuf))
 764         {
 765                 int state = CIT_OK;
 766                 restart_server = extract_int(argbuf, 0);
 767
 768                 if (restart_server > 0)
 769                 {
 770                         Reply = "%d citserver will now shut down and automatically restart.\n";
 771                 }
 772                 if ((restart_server > 0) && !running_as_daemon)
 773                 {
 774                         syslog(LOG_ERR, "The user requested restart, but not running as daemon! Geronimooooooo!\n");
 775                         Reply = "%d Warning: citserver is not running in daemon mode and is therefore unlikely to restart automatically.\n";
 776                         state = ERROR;
 777                 }
 778                 cprintf(Reply, state);
 779         }
 780         else
 781         {
 782                 cprintf(Reply, CIT_OK + SERVER_SHUTTING_DOWN);
 783         }
 784         CC->kill_me = KILLME_SERVER_SHUTTING_DOWN;
 785         server_shutting_down = 1;
 786 }
 787
 788
 789 /*
 790  * Halt the server without exiting the server process.
 791  */
 792 void cmd_halt(char *argbuf) {
 793
 794         if (CtdlAccessCheck(ac_aide)) return;
 795
 796         cprintf("%d Halting server.  Goodbye.\n", CIT_OK);
 797         server_shutting_down = 1;
 798         shutdown_and_halt = 1;
 799 }
 800
 801
 802 /*
 803  * Schedule or cancel a server shutdown
 804  */
 805 void cmd_scdn(char *argbuf)
 806 {
 807         int new_state;
 808         int state = CIT_OK;
 809         char *Reply = "%d %d\n";
 810
 811         if (CtdlAccessCheck(ac_aide)) return;
 812
 813         new_state = extract_int(argbuf, 0);
 814         if ((new_state == 2) || (new_state == 3))
 815         {
 816                 restart_server = 1;
 817                 if (!running_as_daemon)
 818                 {
 819                         syslog(LOG_ERR, "The user requested restart, but not running as deamon! Geronimooooooo!\n");
 820                         Reply = "%d %d Warning, not running in deamon mode. maybe we will come up again, but don't lean on it.\n";
 821                         state = ERROR;
 822                 }
 823
 824                 restart_server = extract_int(argbuf, 0);
 825                 new_state -= 2;
 826         }
 827         if ((new_state == 0) || (new_state == 1)) {
 828                 ScheduledShutdown = new_state;
 829         }
 830         cprintf(Reply, state, ScheduledShutdown);
 831 }
 832
 833
 834 /*
 835  * Set or unset asynchronous protocol mode
 836  */
 837 void cmd_asyn(char *argbuf)
 838 {
 839         int new_state;
 840
 841         new_state = extract_int(argbuf, 0);
 842         if ((new_state == 0) || (new_state == 1)) {
 843                 CC->is_async = new_state;
 844         }
 845         cprintf("%d %d\n", CIT_OK, CC->is_async);
 846 }
 847
 848
 849
 850 /*
 851  * Back-end function for starting a session
 852  */
 853 void begin_session(CitContext *con)
 854 {
 855         /*
 856          * Initialize some variables specific to our context.
 857          */
 858         con->logged_in = 0;
 859         con->internal_pgm = 0;
 860         con->download_fp = NULL;
 861         con->upload_fp = NULL;
 862         con->cached_msglist = NULL;
 863         con->cached_num_msgs = 0;
 864         con->FirstExpressMessage = NULL;
 865         time(&con->lastcmd);
 866         time(&con->lastidle);
 867         strcpy(con->lastcmdname, "    ");
 868         strcpy(con->cs_clientname, "(unknown)");
 869         strcpy(con->curr_user, NLI);
 870         *con->net_node = '\0';
 871         *con->fake_username = '\0';
 872         *con->fake_hostname = '\0';
 873         *con->fake_roomname = '\0';
 874         *con->cs_clientinfo = '\0';
 875         safestrncpy(con->cs_host, config.c_fqdn, sizeof con->cs_host);
 876         safestrncpy(con->cs_addr, "", sizeof con->cs_addr);
 877         con->cs_UDSclientUID = -1;
 878         con->cs_host[sizeof con->cs_host - 1] = 0;
 879         if (!CC->is_local_socket) {
 880                 locate_host(con->cs_host, sizeof con->cs_host,
 881                         con->cs_addr, sizeof con->cs_addr,
 882                         con->client_socket
 883                 );
 884         }
 885         else {
 886                 con->cs_host[0] = 0;
 887                 con->cs_addr[0] = 0;
 888 #ifdef HAVE_STRUCT_UCRED
 889                 {
 890                         /* as http://www.wsinnovations.com/softeng/articles/uds.html told us... */
 891                         struct ucred credentials;
 892                         socklen_t ucred_length = sizeof(struct ucred);
 893
 894                         /*fill in the user data structure */
 895                         if(getsockopt(con->client_socket, SOL_SOCKET, SO_PEERCRED, &credentials, &ucred_length)) {
 896                                 syslog(LOG_NOTICE, "could obtain credentials from unix domain socket");
 897
 898                         }
 899                         else {
 900                                 /* the process ID of the process on the other side of the socket */
 901                                 /* credentials.pid; */
 902
 903                                 /* the effective UID of the process on the other side of the socket  */
 904                                 con->cs_UDSclientUID = credentials.uid;
 905
 906                                 /* the effective primary GID of the process on the other side of the socket */
 907                                 /* credentials.gid; */
 908
 909                                 /* To get supplemental groups, we will have to look them up in our account
 910                                    database, after a reverse lookup on the UID to get the account name.
 911                                    We can take this opportunity to check to see if this is a legit account.
 912                                 */
 913                                 snprintf(con->cs_clientinfo, sizeof(con->cs_clientinfo),
 914                                          "PID: "F_PID_T"; UID: "F_UID_T"; GID: "F_XPID_T" ",
 915                                          credentials.pid,
 916                                          credentials.uid,
 917                                          credentials.gid);
 918                         }
 919                 }
 920 #endif
 921         }
 922         con->cs_flags = 0;
 923         con->upload_type = UPL_FILE;
 924         con->dl_is_net = 0;
 925
 926         con->nologin = 0;
 927         if (((config.c_maxsessions > 0)&&(num_sessions > config.c_maxsessions)) || CtdlWantSingleUser()) {
 928                 con->nologin = 1;
 929         }
 930
 931         if (!CC->is_local_socket) {
 932                 syslog(LOG_NOTICE, "Session (%s) started from %s (%s).\n", con->ServiceName, con->cs_host, con->cs_addr);
 933         }
 934         else {
 935                 syslog(LOG_NOTICE, "Session (%s) started via local socket UID:%d.\n", con->ServiceName, con->cs_UDSclientUID);
 936         }
 937
 938         /* Run any session startup routines registered by loadable modules */
 939         PerformSessionHooks(EVT_START);
 940 }
 941
 942
 943 void citproto_begin_session() {
 944         if (CC->nologin==1) {
 945                 cprintf("%d %s: Too many users are already online (maximum is %d)\n",
 946                         ERROR + MAX_SESSIONS_EXCEEDED,
 947                         config.c_nodename, config.c_maxsessions
 948                 );
 949                 CC->kill_me = KILLME_MAX_SESSIONS_EXCEEDED;
 950         }
 951         else {
 952                 cprintf("%d %s Citadel server ready.\n", CIT_OK, config.c_nodename);
 953                 CC->can_receive_im = 1;
 954         }
 955 }
 956
 957
 958 void citproto_begin_admin_session() {
 959         CC->internal_pgm = 1;
 960         cprintf("%d %s Citadel server ADMIN CONNECTION ready.\n", CIT_OK, config.c_nodename);
 961 }
 962
 963
 964 void cmd_noop(char *argbuf)
 965 {
 966         cprintf("%d%cok\n", CIT_OK, CtdlCheckExpress() );
 967 }
 968
 969
 970 void cmd_qnop(char *argbuf)
 971 {
 972         /* do nothing, this command returns no response */
 973 }
 974
 975
 976 void cmd_quit(char *argbuf)
 977 {
 978         cprintf("%d Goodbye.\n", CIT_OK);
 979         CC->kill_me = KILLME_CLIENT_LOGGED_OUT;
 980 }
 981
 982
 983 void cmd_lout(char *argbuf)
 984 {
 985         if (CC->logged_in)
 986                 CtdlUserLogout();
 987         cprintf("%d logged out.\n", CIT_OK);
 988 }
 989
 990
 991 /*
 992  * This loop recognizes all server commands.
 993  */
 994 void do_command_loop(void) {
 995         char cmdbuf[SIZ];
 996
 997         time(&CC->lastcmd);
 998         memset(cmdbuf, 0, sizeof cmdbuf); /* Clear it, just in case */
 999         if (client_getln(cmdbuf, sizeof cmdbuf) < 1) {
1000                 syslog(LOG_ERR, "Citadel client disconnected: ending session.\n");
1001                 CC->kill_me = KILLME_CLIENT_DISCONNECTED;
1002                 return;
1003         }
1004
1005         /* Log the server command, but don't show passwords... */
1006         if ( (strncasecmp(cmdbuf, "PASS", 4)) && (strncasecmp(cmdbuf, "SETP", 4)) ) {
1007                 syslog(LOG_INFO, "[%d][%s(%ld)] %s",
1008                         CC->cs_pid, CC->curr_user, CC->user.usernum, cmdbuf
1009                 );
1010         }
1011         else {
1012                 syslog(LOG_INFO, "[%d][%s(%ld)] <password command hidden from log>",
1013                         CC->cs_pid, CC->curr_user, CC->user.usernum
1014                 );
1015         }
1016
1017         buffer_output();
1018
1019         /*
1020          * Let other clients see the last command we executed, and
1021          * update the idle time, but not NOOP, QNOP, PEXP, GEXP, RWHO, or TIME.
1022          */
1023         if ( (strncasecmp(cmdbuf, "NOOP", 4))
1024            && (strncasecmp(cmdbuf, "QNOP", 4))
1025            && (strncasecmp(cmdbuf, "PEXP", 4))
1026            && (strncasecmp(cmdbuf, "GEXP", 4))
1027            && (strncasecmp(cmdbuf, "RWHO", 4))
1028            && (strncasecmp(cmdbuf, "TIME", 4)) ) {
1029                 strcpy(CC->lastcmdname, "    ");
1030                 safestrncpy(CC->lastcmdname, cmdbuf, sizeof(CC->lastcmdname));
1031                 time(&CC->lastidle);
1032         }
1033
1034         if ((strncasecmp(cmdbuf, "ENT0", 4))
1035            && (strncasecmp(cmdbuf, "MESG", 4))
1036            && (strncasecmp(cmdbuf, "MSGS", 4)))
1037         {
1038            CC->cs_flags &= ~CS_POSTING;
1039         }
1040
1041         if (!DLoader_Exec_Cmd(cmdbuf)) {
1042                 cprintf("%d Unrecognized or unsupported command.\n", ERROR + CMD_NOT_SUPPORTED);
1043         }
1044
1045         unbuffer_output();
1046
1047         /* Run any after-each-command routines registered by modules */
1048         PerformSessionHooks(EVT_CMD);
1049 }
1050
1051
1052 /*
1053  * This loop performs all asynchronous functions.
1054  */
1055 void do_async_loop(void) {
1056         PerformSessionHooks(EVT_ASYNC);
1057 }
1058
1059
1060 /*****************************************************************************/
1061 /*                      MODULE INITIALIZATION STUFF                          */
1062 /*****************************************************************************/
1063
1064 CTDL_MODULE_INIT(citserver)
1065 {
1066         if (!threading) {
1067                 CtdlRegisterProtoHook(cmd_noop, "NOOP", "no operation");
1068                 CtdlRegisterProtoHook(cmd_qnop, "QNOP", "no operation with no response");
1069                 CtdlRegisterProtoHook(cmd_quit, "QUIT", "log out and disconnect from server");
1070                 CtdlRegisterProtoHook(cmd_lout, "LOUT", "log out but do not disconnect from server");
1071                 CtdlRegisterProtoHook(cmd_asyn, "ASYN", "enable asynchronous server responses");
1072                 CtdlRegisterProtoHook(cmd_info, "INFO", "fetch server capabilities and configuration");
1073                 CtdlRegisterProtoHook(cmd_mesg, "MESG", "fetch system banners");
1074                 CtdlRegisterProtoHook(cmd_emsg, "EMSG", "submit system banners");
1075                 CtdlRegisterProtoHook(cmd_echo, "ECHO", "echo text back to the client");
1076                 CtdlRegisterProtoHook(cmd_more, "MORE", "fetch the paginator prompt");
1077                 CtdlRegisterProtoHook(cmd_iden, "IDEN", "identify the client software and location");
1078                 CtdlRegisterProtoHook(cmd_term, "TERM", "terminate another running session");
1079                 CtdlRegisterProtoHook(cmd_down, "DOWN", "perform a server shutdown");
1080                 CtdlRegisterProtoHook(cmd_halt, "HALT", "halt the server without exiting the server process");
1081                 CtdlRegisterProtoHook(cmd_scdn, "SCDN", "schedule or cancel a server shutdown");
1082                 CtdlRegisterProtoHook(cmd_time, "TIME", "fetch the date and time from the server");
1083         }
1084         /* return our id for the Log */
1085         return "citserver";
1086 }