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 typedef const char *ccharp;
 496 /*
 497  * display system messages or help
 498  */
 499 void cmd_mesg(char *mname)
 500 {
 501         FILE *mfp;
 502         char targ[256];
 503         char buf[256];
 504         char buf2[256];
 505         char *dirs[2];
 506         DIR *dp;
 507         struct dirent *d;
 508
 509         extract_token(buf, mname, 0, '|', sizeof buf);
 510
 511         dirs[0] = strdup(ctdl_message_dir);
 512         dirs[1] = strdup(ctdl_hlp_dir);
 513
 514         snprintf(buf2, sizeof buf2, "%s.%d.%d",
 515                 buf, CC->cs_clientdev, CC->cs_clienttyp);
 516
 517         /* If the client requested "?" then produce a listing */
 518         if (!strcmp(buf, "?")) {
 519                 cprintf("%d %s\n", LISTING_FOLLOWS, buf);
 520                 dp = opendir(dirs[1]);
 521                 if (dp != NULL) {
 522                         while (d = readdir(dp), d != NULL) {
 523                                 if (d->d_name[0] != '.') {
 524                                         cprintf(" %s\n", d->d_name);
 525                                 }
 526                         }
 527                         closedir(dp);
 528                 }
 529                 cprintf("000\n");
 530                 free(dirs[0]);
 531                 free(dirs[1]);
 532                 return;
 533         }
 534
 535         /* Otherwise, look for the requested file by name. */
 536         else {
 537                 mesg_locate(targ, sizeof targ, buf2, 2, (const ccharp*)dirs);
 538                 if (IsEmptyStr(targ)) {
 539                         snprintf(buf2, sizeof buf2, "%s.%d",
 540                                                         buf, CC->cs_clientdev);
 541                         mesg_locate(targ, sizeof targ, buf2, 2,
 542                                     (const ccharp*)dirs);
 543                         if (IsEmptyStr(targ)) {
 544                                 mesg_locate(targ, sizeof targ, buf, 2,
 545                                             (const ccharp*)dirs);
 546                         }
 547                 }
 548         }
 549
 550         free(dirs[0]);
 551         free(dirs[1]);
 552
 553         if (IsEmptyStr(targ)) {
 554                 cprintf("%d '%s' not found.  (Searching in %s and %s)\n",
 555                         ERROR + FILE_NOT_FOUND,
 556                         mname,
 557                         ctdl_message_dir,
 558                         ctdl_hlp_dir
 559                 );
 560                 return;
 561         }
 562
 563         mfp = fopen(targ, "r");
 564         if (mfp==NULL) {
 565                 cprintf("%d Cannot open '%s': %s\n",
 566                         ERROR + INTERNAL_ERROR, targ, strerror(errno));
 567                 return;
 568         }
 569         cprintf("%d %s\n", LISTING_FOLLOWS,buf);
 570
 571         while (fgets(buf, (sizeof buf - 1), mfp) != NULL) {
 572                 buf[strlen(buf)-1] = 0;
 573                 do_help_subst(buf);
 574                 cprintf("%s\n",buf);
 575         }
 576
 577         fclose(mfp);
 578         cprintf("000\n");
 579 }
 580
 581
 582 /*
 583  * enter system messages or help
 584  */
 585 void cmd_emsg(char *mname)
 586 {
 587         FILE *mfp;
 588         char targ[256];
 589         char buf[256];
 590         char *dirs[2];
 591         int a;
 592
 593         unbuffer_output();
 594
 595         if (CtdlAccessCheck(ac_aide)) return;
 596
 597         extract_token(buf, mname, 0, '|', sizeof buf);
 598         for (a=0; !IsEmptyStr(&buf[a]); ++a) {          /* security measure */
 599                 if (buf[a] == '/') buf[a] = '.';
 600         }
 601
 602         dirs[0] = strdup(ctdl_message_dir);
 603         dirs[1] = strdup(ctdl_hlp_dir);
 604
 605         mesg_locate(targ, sizeof targ, buf, 2, (const ccharp*)dirs);
 606         free(dirs[0]);
 607         free(dirs[1]);
 608
 609         if (IsEmptyStr(targ)) {
 610                 snprintf(targ, sizeof targ,
 611                                  "%s/%s",
 612                                  ctdl_hlp_dir, buf);
 613         }
 614
 615         mfp = fopen(targ,"w");
 616         if (mfp==NULL) {
 617                 cprintf("%d Cannot open '%s': %s\n",
 618                         ERROR + INTERNAL_ERROR, targ, strerror(errno));
 619                 return;
 620         }
 621         cprintf("%d %s\n", SEND_LISTING, targ);
 622
 623         while (client_getln(buf, sizeof buf) >=0 && strcmp(buf, "000")) {
 624                 fprintf(mfp, "%s\n", buf);
 625         }
 626
 627         fclose(mfp);
 628 }
 629
 630
 631 /* Don't show the names of private rooms unless the viewing
 632  * user also knows the rooms.
 633  */
 634 void GenerateRoomDisplay(char *real_room,
 635                         CitContext *viewed,
 636                         CitContext *viewer) {
 637
 638         int ra;
 639
 640         strcpy(real_room, viewed->room.QRname);
 641         if (viewed->room.QRflags & QR_MAILBOX) {
 642                 strcpy(real_room, &real_room[11]);
 643         }
 644         if (viewed->room.QRflags & QR_PRIVATE) {
 645                 CtdlRoomAccess(&viewed->room, &viewer->user, &ra, NULL);
 646                 if ( (ra & UA_KNOWN) == 0) {
 647                         strcpy(real_room, " ");
 648                 }
 649         }
 650
 651         if (viewed->cs_flags & CS_CHAT) {
 652                 while (strlen(real_room) < 14) {
 653                         strcat(real_room, " ");
 654                 }
 655                 strcpy(&real_room[14], "<chat>");
 656         }
 657
 658 }
 659
 660 /*
 661  * Convenience function.
 662  */
 663 int CtdlAccessCheck(int required_level) {
 664
 665         if (CC->internal_pgm) return(0);
 666         if (required_level >= ac_internal) {
 667                 cprintf("%d This is not a user-level command.\n",
 668                         ERROR + HIGHER_ACCESS_REQUIRED);
 669                 return(-1);
 670         }
 671
 672         if ((required_level >= ac_logged_in_or_guest) && (CC->logged_in == 0) && (!config.c_guest_logins)) {
 673                 cprintf("%d Not logged in.\n", ERROR + NOT_LOGGED_IN);
 674                 return(-1);
 675         }
 676
 677         if ((required_level >= ac_logged_in) && (CC->logged_in == 0)) {
 678                 cprintf("%d Not logged in.\n", ERROR + NOT_LOGGED_IN);
 679                 return(-1);
 680         }
 681
 682         if (CC->user.axlevel >= AxAideU) return(0);
 683         if (required_level >= ac_aide) {
 684                 cprintf("%d This command requires Admin access.\n",
 685                         ERROR + HIGHER_ACCESS_REQUIRED);
 686                 return(-1);
 687         }
 688
 689         if (is_room_aide()) return(0);
 690         if (required_level >= ac_room_aide) {
 691                 cprintf("%d This command requires Admin or Room Admin access.\n",
 692                         ERROR + HIGHER_ACCESS_REQUIRED);
 693                 return(-1);
 694         }
 695
 696         /* shhh ... succeed quietly */
 697         return(0);
 698 }
 699
 700
 701
 702 /*
 703  * Terminate another running session
 704  */
 705 void cmd_term(char *cmdbuf)
 706 {
 707         int session_num;
 708         int terminated = 0;
 709
 710         session_num = extract_int(cmdbuf, 0);
 711
 712         terminated = CtdlTerminateOtherSession(session_num);
 713
 714         if (terminated < 0) {
 715                 cprintf("%d You can't kill your own session.\n", ERROR + ILLEGAL_VALUE);
 716                 return;
 717         }
 718
 719         if (terminated & TERM_FOUND) {
 720                 if (terminated == TERM_KILLED) {
 721                         cprintf("%d Session terminated.\n", CIT_OK);
 722                 }
 723                 else {
 724                         cprintf("%d You are not allowed to do that.\n",
 725                                 ERROR + HIGHER_ACCESS_REQUIRED);
 726                 }
 727         }
 728         else {
 729                 cprintf("%d No such session.\n", ERROR + ILLEGAL_VALUE);
 730         }
 731 }
 732
 733
 734 /*
 735  * get the paginator prompt
 736  */
 737 void cmd_more(char *argbuf) {
 738         cprintf("%d %s\n", CIT_OK, config.c_moreprompt);
 739 }
 740
 741
 742 /*
 743  * echo
 744  */
 745 void cmd_echo(char *etext)
 746 {
 747         cprintf("%d %s\n", CIT_OK, etext);
 748 }
 749
 750
 751
 752 /*
 753  * Shut down the server
 754  */
 755 void cmd_down(char *argbuf) {
 756         char *Reply ="%d Shutting down server.  Goodbye.\n";
 757
 758         if (CtdlAccessCheck(ac_aide)) return;
 759
 760         if (!IsEmptyStr(argbuf))
 761         {
 762                 int state = CIT_OK;
 763                 restart_server = extract_int(argbuf, 0);
 764
 765                 if (restart_server > 0)
 766                 {
 767                         Reply = "%d citserver will now shut down and automatically restart.\n";
 768                 }
 769                 if ((restart_server > 0) && !running_as_daemon)
 770                 {
 771                         syslog(LOG_ERR, "The user requested restart, but not running as daemon! Geronimooooooo!\n");
 772                         Reply = "%d Warning: citserver is not running in daemon mode and is therefore unlikely to restart automatically.\n";
 773                         state = ERROR;
 774                 }
 775                 cprintf(Reply, state);
 776         }
 777         else
 778         {
 779                 cprintf(Reply, CIT_OK + SERVER_SHUTTING_DOWN);
 780         }
 781         CC->kill_me = KILLME_SERVER_SHUTTING_DOWN;
 782         server_shutting_down = 1;
 783 }
 784
 785
 786 /*
 787  * Halt the server without exiting the server process.
 788  */
 789 void cmd_halt(char *argbuf) {
 790
 791         if (CtdlAccessCheck(ac_aide)) return;
 792
 793         cprintf("%d Halting server.  Goodbye.\n", CIT_OK);
 794         server_shutting_down = 1;
 795         shutdown_and_halt = 1;
 796 }
 797
 798
 799 /*
 800  * Schedule or cancel a server shutdown
 801  */
 802 void cmd_scdn(char *argbuf)
 803 {
 804         int new_state;
 805         int state = CIT_OK;
 806         char *Reply = "%d %d\n";
 807
 808         if (CtdlAccessCheck(ac_aide)) return;
 809
 810         new_state = extract_int(argbuf, 0);
 811         if ((new_state == 2) || (new_state == 3))
 812         {
 813                 restart_server = 1;
 814                 if (!running_as_daemon)
 815                 {
 816                         syslog(LOG_ERR, "The user requested restart, but not running as deamon! Geronimooooooo!\n");
 817                         Reply = "%d %d Warning, not running in deamon mode. maybe we will come up again, but don't lean on it.\n";
 818                         state = ERROR;
 819                 }
 820
 821                 restart_server = extract_int(argbuf, 0);
 822                 new_state -= 2;
 823         }
 824         if ((new_state == 0) || (new_state == 1)) {
 825                 ScheduledShutdown = new_state;
 826         }
 827         cprintf(Reply, state, ScheduledShutdown);
 828 }
 829
 830
 831 /*
 832  * Set or unset asynchronous protocol mode
 833  */
 834 void cmd_asyn(char *argbuf)
 835 {
 836         int new_state;
 837
 838         new_state = extract_int(argbuf, 0);
 839         if ((new_state == 0) || (new_state == 1)) {
 840                 CC->is_async = new_state;
 841         }
 842         cprintf("%d %d\n", CIT_OK, CC->is_async);
 843 }
 844
 845
 846
 847 /*
 848  * Back-end function for starting a session
 849  */
 850 void begin_session(CitContext *con)
 851 {
 852         /*
 853          * Initialize some variables specific to our context.
 854          */
 855         con->logged_in = 0;
 856         con->internal_pgm = 0;
 857         con->download_fp = NULL;
 858         con->upload_fp = NULL;
 859         con->cached_msglist = NULL;
 860         con->cached_num_msgs = 0;
 861         con->FirstExpressMessage = NULL;
 862         time(&con->lastcmd);
 863         time(&con->lastidle);
 864         strcpy(con->lastcmdname, "    ");
 865         strcpy(con->cs_clientname, "(unknown)");
 866         strcpy(con->curr_user, NLI);
 867         *con->net_node = '\0';
 868         *con->fake_username = '\0';
 869         *con->fake_hostname = '\0';
 870         *con->fake_roomname = '\0';
 871         *con->cs_clientinfo = '\0';
 872         safestrncpy(con->cs_host, config.c_fqdn, sizeof con->cs_host);
 873         safestrncpy(con->cs_addr, "", sizeof con->cs_addr);
 874         con->cs_UDSclientUID = -1;
 875         con->cs_host[sizeof con->cs_host - 1] = 0;
 876         if (!CC->is_local_socket) {
 877                 locate_host(con->cs_host, sizeof con->cs_host,
 878                         con->cs_addr, sizeof con->cs_addr,
 879                         con->client_socket
 880                 );
 881         }
 882         else {
 883                 con->cs_host[0] = 0;
 884                 con->cs_addr[0] = 0;
 885 #ifdef HAVE_STRUCT_UCRED
 886                 {
 887                         /* as http://www.wsinnovations.com/softeng/articles/uds.html told us... */
 888                         struct ucred credentials;
 889                         socklen_t ucred_length = sizeof(struct ucred);
 890
 891                         /*fill in the user data structure */
 892                         if(getsockopt(con->client_socket, SOL_SOCKET, SO_PEERCRED, &credentials, &ucred_length)) {
 893                                 syslog(LOG_NOTICE, "could obtain credentials from unix domain socket");
 894
 895                         }
 896                         else {
 897                                 /* the process ID of the process on the other side of the socket */
 898                                 /* credentials.pid; */
 899
 900                                 /* the effective UID of the process on the other side of the socket  */
 901                                 con->cs_UDSclientUID = credentials.uid;
 902
 903                                 /* the effective primary GID of the process on the other side of the socket */
 904                                 /* credentials.gid; */
 905
 906                                 /* To get supplemental groups, we will have to look them up in our account
 907                                    database, after a reverse lookup on the UID to get the account name.
 908                                    We can take this opportunity to check to see if this is a legit account.
 909                                 */
 910                                 snprintf(con->cs_clientinfo, sizeof(con->cs_clientinfo),
 911                                          "PID: "F_PID_T"; UID: "F_UID_T"; GID: "F_XPID_T" ",
 912                                          credentials.pid,
 913                                          credentials.uid,
 914                                          credentials.gid);
 915                         }
 916                 }
 917 #endif
 918         }
 919         con->cs_flags = 0;
 920         con->upload_type = UPL_FILE;
 921         con->dl_is_net = 0;
 922
 923         con->nologin = 0;
 924         if (((config.c_maxsessions > 0)&&(num_sessions > config.c_maxsessions)) || CtdlWantSingleUser()) {
 925                 con->nologin = 1;
 926         }
 927
 928         if (!CC->is_local_socket) {
 929                 syslog(LOG_NOTICE, "Session (%s) started from %s (%s).\n", con->ServiceName, con->cs_host, con->cs_addr);
 930         }
 931         else {
 932                 syslog(LOG_NOTICE, "Session (%s) started via local socket UID:%d.\n", con->ServiceName, con->cs_UDSclientUID);
 933         }
 934
 935         /* Run any session startup routines registered by loadable modules */
 936         PerformSessionHooks(EVT_START);
 937 }
 938
 939
 940 void citproto_begin_session() {
 941         if (CC->nologin==1) {
 942                 cprintf("%d %s: Too many users are already online (maximum is %d)\n",
 943                         ERROR + MAX_SESSIONS_EXCEEDED,
 944                         config.c_nodename, config.c_maxsessions
 945                 );
 946                 CC->kill_me = KILLME_MAX_SESSIONS_EXCEEDED;
 947         }
 948         else {
 949                 cprintf("%d %s Citadel server ready.\n", CIT_OK, config.c_nodename);
 950                 CC->can_receive_im = 1;
 951         }
 952 }
 953
 954
 955 void citproto_begin_admin_session() {
 956         CC->internal_pgm = 1;
 957         cprintf("%d %s Citadel server ADMIN CONNECTION ready.\n", CIT_OK, config.c_nodename);
 958 }
 959
 960
 961 void cmd_noop(char *argbuf)
 962 {
 963         cprintf("%d%cok\n", CIT_OK, CtdlCheckExpress() );
 964 }
 965
 966
 967 void cmd_qnop(char *argbuf)
 968 {
 969         /* do nothing, this command returns no response */
 970 }
 971
 972
 973 void cmd_quit(char *argbuf)
 974 {
 975         cprintf("%d Goodbye.\n", CIT_OK);
 976         CC->kill_me = KILLME_CLIENT_LOGGED_OUT;
 977 }
 978
 979
 980 void cmd_lout(char *argbuf)
 981 {
 982         if (CC->logged_in)
 983                 CtdlUserLogout();
 984         cprintf("%d logged out.\n", CIT_OK);
 985 }
 986
 987
 988 /*
 989  * This loop recognizes all server commands.
 990  */
 991 void do_command_loop(void) {
 992         char cmdbuf[SIZ];
 993
 994         time(&CC->lastcmd);
 995         memset(cmdbuf, 0, sizeof cmdbuf); /* Clear it, just in case */
 996         if (client_getln(cmdbuf, sizeof cmdbuf) < 1) {
 997                 syslog(LOG_ERR, "Citadel client disconnected: ending session.\n");
 998                 CC->kill_me = KILLME_CLIENT_DISCONNECTED;
 999                 return;
1000         }
1001
1002         /* Log the server command, but don't show passwords... */
1003         if ( (strncasecmp(cmdbuf, "PASS", 4)) && (strncasecmp(cmdbuf, "SETP", 4)) ) {
1004                 syslog(LOG_INFO, "[%d][%s(%ld)] %s",
1005                         CC->cs_pid, CC->curr_user, CC->user.usernum, cmdbuf
1006                 );
1007         }
1008         else {
1009                 syslog(LOG_INFO, "[%d][%s(%ld)] <password command hidden from log>",
1010                         CC->cs_pid, CC->curr_user, CC->user.usernum
1011                 );
1012         }
1013
1014         buffer_output();
1015
1016         /*
1017          * Let other clients see the last command we executed, and
1018          * update the idle time, but not NOOP, QNOP, PEXP, GEXP, RWHO, or TIME.
1019          */
1020         if ( (strncasecmp(cmdbuf, "NOOP", 4))
1021            && (strncasecmp(cmdbuf, "QNOP", 4))
1022            && (strncasecmp(cmdbuf, "PEXP", 4))
1023            && (strncasecmp(cmdbuf, "GEXP", 4))
1024            && (strncasecmp(cmdbuf, "RWHO", 4))
1025            && (strncasecmp(cmdbuf, "TIME", 4)) ) {
1026                 strcpy(CC->lastcmdname, "    ");
1027                 safestrncpy(CC->lastcmdname, cmdbuf, sizeof(CC->lastcmdname));
1028                 time(&CC->lastidle);
1029         }
1030
1031         if ((strncasecmp(cmdbuf, "ENT0", 4))
1032            && (strncasecmp(cmdbuf, "MESG", 4))
1033            && (strncasecmp(cmdbuf, "MSGS", 4)))
1034         {
1035            CC->cs_flags &= ~CS_POSTING;
1036         }
1037
1038         if (!DLoader_Exec_Cmd(cmdbuf)) {
1039                 cprintf("%d Unrecognized or unsupported command.\n", ERROR + CMD_NOT_SUPPORTED);
1040         }
1041
1042         unbuffer_output();
1043
1044         /* Run any after-each-command routines registered by modules */
1045         PerformSessionHooks(EVT_CMD);
1046 }
1047
1048
1049 /*
1050  * This loop performs all asynchronous functions.
1051  */
1052 void do_async_loop(void) {
1053         PerformSessionHooks(EVT_ASYNC);
1054 }
1055
1056
1057 /*****************************************************************************/
1058 /*                      MODULE INITIALIZATION STUFF                          */
1059 /*****************************************************************************/
1060
1061 CTDL_MODULE_INIT(citserver)
1062 {
1063         if (!threading) {
1064                 CtdlRegisterProtoHook(cmd_noop, "NOOP", "no operation");
1065                 CtdlRegisterProtoHook(cmd_qnop, "QNOP", "no operation with no response");
1066                 CtdlRegisterProtoHook(cmd_quit, "QUIT", "log out and disconnect from server");
1067                 CtdlRegisterProtoHook(cmd_lout, "LOUT", "log out but do not disconnect from server");
1068                 CtdlRegisterProtoHook(cmd_asyn, "ASYN", "enable asynchronous server responses");
1069                 CtdlRegisterProtoHook(cmd_info, "INFO", "fetch server capabilities and configuration");
1070                 CtdlRegisterProtoHook(cmd_mesg, "MESG", "fetch system banners");
1071                 CtdlRegisterProtoHook(cmd_emsg, "EMSG", "submit system banners");
1072                 CtdlRegisterProtoHook(cmd_echo, "ECHO", "echo text back to the client");
1073                 CtdlRegisterProtoHook(cmd_more, "MORE", "fetch the paginator prompt");
1074                 CtdlRegisterProtoHook(cmd_iden, "IDEN", "identify the client software and location");
1075                 CtdlRegisterProtoHook(cmd_term, "TERM", "terminate another running session");
1076                 CtdlRegisterProtoHook(cmd_down, "DOWN", "perform a server shutdown");
1077                 CtdlRegisterProtoHook(cmd_halt, "HALT", "halt the server without exiting the server process");
1078                 CtdlRegisterProtoHook(cmd_scdn, "SCDN", "schedule or cancel a server shutdown");
1079                 CtdlRegisterProtoHook(cmd_time, "TIME", "fetch the date and time from the server");
1080         }
1081         /* return our id for the Log */
1082         return "citserver";
1083 }