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