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 as published by
   8  * the Free Software Foundation; either version 3 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  19  */
  20
  21 #include "sysdep.h"
  22 #include <stdlib.h>
  23 #include <unistd.h>
  24 #include <stdio.h>
  25 #include <fcntl.h>
  26 #include <signal.h>
  27 #include <sys/types.h>
  28 #include <sys/stat.h>
  29
  30 #if TIME_WITH_SYS_TIME
  31 # include <sys/time.h>
  32 # include <time.h>
  33 #else
  34 # if HAVE_SYS_TIME_H
  35 #  include <sys/time.h>
  36 # else
  37 #  include <time.h>
  38 # endif
  39 #endif
  40
  41 #if HAVE_BACKTRACE
  42 #include <execinfo.h>
  43 #endif
  44
  45 #include <ctype.h>
  46 #include <string.h>
  47 #include <dirent.h>
  48 #include <errno.h>
  49 #include <limits.h>
  50 #include <netdb.h>
  51 #include <sys/types.h>
  52 #include <sys/socket.h>
  53 #include <netinet/in.h>
  54 #include <arpa/inet.h>
  55 #include <libcitadel.h>
  56 #include "citadel.h"
  57 #include "server.h"
  58 #include "sysdep_decls.h"
  59 #include "threads.h"
  60 #include "citserver.h"
  61 #include "config.h"
  62 #include "database.h"
  63 #include "housekeeping.h"
  64 #include "user_ops.h"
  65 #include "msgbase.h"
  66 #include "support.h"
  67 #include "locate_host.h"
  68 #include "room_ops.h"
  69 #include "file_ops.h"
  70 #include "control.h"
  71 #include "euidindex.h"
  72 #include "context.h"
  73 #include "svn_revision.h"
  74
  75 #ifndef HAVE_SNPRINTF
  76 #include "snprintf.h"
  77 #endif
  78
  79 #include "ctdl_module.h"
  80
  81 char *unique_session_numbers;
  82 int ScheduledShutdown = 0;
  83 time_t server_startup_time;
  84 int panic_fd;
  85 int openid_level_supported = 0;
  86
  87 /*
  88  * print the actual stack frame.
  89  */
  90 void cit_backtrace(void)
  91 {
  92 #ifdef HAVE_BACKTRACE
  93         void *stack_frames[50];
  94         size_t size, i;
  95         char **strings;
  96
  97
  98         size = backtrace(stack_frames, sizeof(stack_frames) / sizeof(void*));
  99         strings = backtrace_symbols(stack_frames, size);
 100         for (i = 0; i < size; i++) {
 101                 if (strings != NULL)
 102                         syslog(LOG_ALERT, "%s\n", strings[i]);
 103                 else
 104                         syslog(LOG_ALERT, "%p\n", stack_frames[i]);
 105         }
 106         free(strings);
 107 #endif
 108 }
 109
 110 void cit_oneline_backtrace(void)
 111 {
 112 #ifdef HAVE_BACKTRACE
 113         void *stack_frames[50];
 114         size_t size, i;
 115         char **strings;
 116         StrBuf *Buf;
 117
 118         size = backtrace(stack_frames, sizeof(stack_frames) / sizeof(void*));
 119         strings = backtrace_symbols(stack_frames, size);
 120         if (size > 0)
 121         {
 122                 Buf = NewStrBuf();
 123                 for (i = 1; i < size; i++) {
 124                         if (strings != NULL)
 125                                 StrBufAppendPrintf(Buf, "%s : ", strings[i]);
 126                         else
 127                                 StrBufAppendPrintf(Buf, "%p : ", stack_frames[i]);
 128                 }
 129                 free(strings);
 130                 syslog(LOG_ALERT, "%s\n", ChrPtr(Buf));
 131                 FreeStrBuf(&Buf);
 132         }
 133 #endif
 134 }
 135
 136 /*
 137  * print the actual stack frame.
 138  */
 139 void cit_panic_backtrace(int SigNum)
 140 {
 141 #ifdef HAVE_BACKTRACE
 142         void *stack_frames[10];
 143         size_t size, i;
 144         char **strings;
 145
 146         printf("caught signal 11\n");
 147         size = backtrace(stack_frames, sizeof(stack_frames) / sizeof(void*));
 148         strings = backtrace_symbols(stack_frames, size);
 149         for (i = 0; i < size; i++) {
 150                 if (strings != NULL)
 151                         syslog(LOG_ALERT, "%s\n", strings[i]);
 152                 else
 153                         syslog(LOG_ALERT, "%p\n", stack_frames[i]);
 154         }
 155         free(strings);
 156 #endif
 157         exit(-1);
 158 }
 159
 160 /*
 161  * Various things that need to be initialized at startup
 162  */
 163 void master_startup(void) {
 164         struct timeval tv;
 165         unsigned int seed;
 166         FILE *urandom;
 167         struct ctdlroom qrbuf;
 168         int rv;
 169
 170         syslog(LOG_DEBUG, "master_startup() started\n");
 171         time(&server_startup_time);
 172         get_config();
 173
 174         syslog(LOG_INFO, "Opening databases\n");
 175         open_databases();
 176         check_ref_counts();
 177
 178         syslog(LOG_INFO, "Creating base rooms (if necessary)\n");
 179         CtdlCreateRoom(config.c_baseroom,       0, "", 0, 1, 0, VIEW_BBS);
 180         CtdlCreateRoom(AIDEROOM,                3, "", 0, 1, 0, VIEW_BBS);
 181         CtdlCreateRoom(SYSCONFIGROOM,           3, "", 0, 1, 0, VIEW_BBS);
 182         CtdlCreateRoom(config.c_twitroom,       0, "", 0, 1, 0, VIEW_BBS);
 183
 184         /* The "Local System Configuration" room doesn't need to be visible */
 185         if (CtdlGetRoomLock(&qrbuf, SYSCONFIGROOM) == 0) {
 186                 qrbuf.QRflags2 |= QR2_SYSTEM;
 187                 CtdlPutRoomLock(&qrbuf);
 188         }
 189
 190         /* Aide needs to be public postable, else we're not RFC conformant. */
 191         if (CtdlGetRoomLock(&qrbuf, AIDEROOM) == 0) {
 192                 qrbuf.QRflags2 |= QR2_SMTP_PUBLIC;
 193                 CtdlPutRoomLock(&qrbuf);
 194         }
 195
 196         syslog(LOG_INFO, "Seeding the pseudo-random number generator...\n");
 197         urandom = fopen("/dev/urandom", "r");
 198         if (urandom != NULL) {
 199                 rv = fread(&seed, sizeof seed, 1, urandom);
 200                 if (rv == -1)
 201                         syslog(LOG_EMERG, "failed to read random seed: %s\n",
 202                                strerror(errno));
 203                 fclose(urandom);
 204         }
 205         else {
 206                 gettimeofday(&tv, NULL);
 207                 seed = tv.tv_usec;
 208         }
 209         srand(seed);
 210         srandom(seed);
 211
 212         put_config();
 213
 214         syslog(LOG_DEBUG, "master_startup() finished\n");
 215 }
 216
 217
 218 /*
 219  * Cleanup routine to be called when the server is shutting down.
 220  */
 221 void master_cleanup(int exitcode) {
 222         struct CleanupFunctionHook *fcn;
 223         static int already_cleaning_up = 0;
 224
 225         if (already_cleaning_up) while(1) usleep(1000);
 226         already_cleaning_up = 1;
 227
 228         /* Run any cleanup routines registered by loadable modules */
 229         for (fcn = CleanupHookTable; fcn != NULL; fcn = fcn->next) {
 230                 (*fcn->h_function_pointer)();
 231         }
 232
 233         /* Close the AdjRefCount queue file */
 234         AdjRefCount(-1, 0);
 235
 236         /* Do system-dependent stuff */
 237         sysdep_master_cleanup();
 238
 239         /* Close databases */
 240         syslog(LOG_INFO, "Closing databases\n");
 241         close_databases();
 242
 243         /* If the operator requested a halt but not an exit, halt here. */
 244         if (shutdown_and_halt) {
 245                 syslog(LOG_NOTICE, "citserver: Halting server without exiting.\n");
 246                 fflush(stdout); fflush(stderr);
 247                 while(1) {
 248                         sleep(32767);
 249                 }
 250         }
 251
 252         release_control();
 253
 254         /* Now go away. */
 255         syslog(LOG_NOTICE, "citserver: Exiting with status %d\n", exitcode);
 256         fflush(stdout); fflush(stderr);
 257
 258         if (restart_server != 0)
 259                 exit(1);
 260         if ((running_as_daemon != 0) && ((exitcode == 0) ))
 261                 exitcode = CTDLEXIT_SHUTDOWN;
 262         exit(exitcode);
 263 }
 264
 265
 266
 267 /*
 268  * cmd_info()  -  tell the client about this server
 269  */
 270 void cmd_info(char *cmdbuf) {
 271         cprintf("%d Server info:\n", LISTING_FOLLOWS);
 272         cprintf("%d\n", CC->cs_pid);
 273         cprintf("%s\n", config.c_nodename);
 274         cprintf("%s\n", config.c_humannode);
 275         cprintf("%s\n", config.c_fqdn);
 276         cprintf("%s\n", CITADEL);
 277         cprintf("%d\n", REV_LEVEL);
 278         cprintf("%s\n", config.c_site_location);
 279         cprintf("%s\n", config.c_sysadm);
 280         cprintf("%d\n", SERVER_TYPE);
 281         cprintf("%s\n", config.c_moreprompt);
 282         cprintf("1\n"); /* 1 = yes, this system supports floors */
 283         cprintf("1\n"); /* 1 = we support the extended paging options */
 284         cprintf("\n");  /* nonce no longer supported */
 285         cprintf("1\n"); /* 1 = yes, this system supports the QNOP command */
 286
 287 #ifdef HAVE_LDAP
 288         cprintf("1\n"); /* 1 = yes, this server is LDAP-enabled */
 289 #else
 290         cprintf("0\n"); /* 1 = no, this server is not LDAP-enabled */
 291 #endif
 292
 293         if (config.c_auth_mode == AUTHMODE_NATIVE) {
 294                 cprintf("%d\n", config.c_disable_newu);
 295         }
 296         else {
 297                 cprintf("1\n"); /* "create new user" does not work with non-native auth modes */
 298         }
 299
 300         cprintf("%s\n", config.c_default_cal_zone);
 301
 302         /* thread load averages -- temporarily disabled during refactoring of this code */
 303         cprintf("0\n");         /* load average */
 304         cprintf("0\n");         /* worker average */
 305         cprintf("0\n");         /* thread count */
 306
 307         cprintf("1\n");         /* yes, Sieve mail filtering is supported */
 308         cprintf("%d\n", config.c_enable_fulltext);
 309         cprintf("%s\n", svn_revision());
 310
 311         if (config.c_auth_mode == AUTHMODE_NATIVE) {
 312                 cprintf("%d\n", openid_level_supported); /* OpenID is enabled when using native auth */
 313         }
 314         else {
 315                 cprintf("0\n"); /* OpenID is disabled when using non-native auth */
 316         }
 317
 318         cprintf("%d\n", config.c_guest_logins);
 319
 320         cprintf("000\n");
 321 }
 322
 323
 324 /*
 325  * returns an asterisk if there are any instant messages waiting,
 326  * space otherwise.
 327  */
 328 char CtdlCheckExpress(void) {
 329         if (CC->FirstExpressMessage == NULL) {
 330                 return(' ');
 331         }
 332         else {
 333                 return('*');
 334         }
 335 }
 336
 337 void cmd_time(char *argbuf)
 338 {
 339    time_t tv;
 340    struct tm tmp;
 341
 342    tv = time(NULL);
 343    localtime_r(&tv, &tmp);
 344
 345    /* timezone and daylight global variables are not portable. */
 346 #ifdef HAVE_STRUCT_TM_TM_GMTOFF
 347    cprintf("%d %ld|%ld|%d|%ld\n", CIT_OK, (long)tv, tmp.tm_gmtoff, tmp.tm_isdst, server_startup_time);
 348 #else
 349    cprintf("%d %ld|%ld|%d|%ld\n", CIT_OK, (long)tv, timezone, tmp.tm_isdst, server_startup_time);
 350 #endif
 351 }
 352
 353
 354 /*
 355  * Check originating host against the public_clients file.  This determines
 356  * whether the client is allowed to change the hostname for this session
 357  * (for example, to show the location of the user rather than the location
 358  * of the client).
 359  */
 360 int is_public_client(void)
 361 {
 362         char buf[1024];
 363         char addrbuf[1024];
 364         FILE *fp;
 365         int i;
 366         char *public_clientspos;
 367         char *public_clientsend;
 368         char *paddr = NULL;
 369         struct stat statbuf;
 370         static time_t pc_timestamp = 0;
 371         static char public_clients[SIZ];
 372         static char public_clients_file[SIZ];
 373
 374 #define LOCALHOSTSTR "127.0.0.1"
 375
 376         snprintf(public_clients_file, sizeof public_clients_file, "%s/public_clients", ctdl_etc_dir);
 377
 378         /*
 379          * Check the time stamp on the public_clients file.  If it's been
 380          * updated since the last time we were here (or if this is the first
 381          * time we've been through the loop), read its contents and learn
 382          * the IP addresses of the listed hosts.
 383          */
 384         if (stat(public_clients_file, &statbuf) != 0) {
 385                 /* No public_clients file exists, so bail out */
 386                 syslog(LOG_WARNING, "Warning: '%s' does not exist\n",
 387                                 public_clients_file);
 388                 return(0);
 389         }
 390
 391         if (statbuf.st_mtime > pc_timestamp) {
 392                 begin_critical_section(S_PUBLIC_CLIENTS);
 393                 syslog(LOG_INFO, "Loading %s\n", public_clients_file);
 394
 395                 public_clientspos = &public_clients[0];
 396                 public_clientsend = public_clientspos + SIZ;
 397                 safestrncpy(public_clientspos, LOCALHOSTSTR, sizeof public_clients);
 398                 public_clientspos += sizeof(LOCALHOSTSTR) - 1;
 399
 400                 if (hostname_to_dotted_quad(addrbuf, config.c_fqdn) == 0) {
 401                         *(public_clientspos++) = '|';
 402                         paddr = &addrbuf[0];
 403                         while (!IsEmptyStr (paddr) &&
 404                                (public_clientspos < public_clientsend))
 405                                 *(public_clientspos++) = *(paddr++);
 406                 }
 407
 408                 fp = fopen(public_clients_file, "r");
 409                 if (fp != NULL)
 410                         while ((fgets(buf, sizeof buf, fp)!=NULL) &&
 411                                (public_clientspos < public_clientsend)){
 412                                 char *ptr;
 413                                 ptr = buf;
 414                                 while (!IsEmptyStr(ptr)) {
 415                                         if (*ptr == '#') {
 416                                                 *ptr = 0;
 417                                                 break;
 418                                         }
 419                                 else ptr++;
 420                                 }
 421                                 ptr--;
 422                                 while (ptr>buf && isspace(*ptr)) {
 423                                         *(ptr--) = 0;
 424                                 }
 425                                 if (hostname_to_dotted_quad(addrbuf, buf) == 0) {
 426                                         *(public_clientspos++) = '|';
 427                                         paddr = addrbuf;
 428                                         while (!IsEmptyStr(paddr) &&
 429                                                (public_clientspos < public_clientsend)){
 430                                                 *(public_clientspos++) = *(paddr++);
 431                                         }
 432                                 }
 433                         }
 434                 fclose(fp);
 435                 pc_timestamp = time(NULL);
 436                 end_critical_section(S_PUBLIC_CLIENTS);
 437         }
 438
 439         syslog(LOG_DEBUG, "Checking whether %s is a local or public client\n",
 440                 CC->cs_addr);
 441         for (i=0; i<num_parms(public_clients); ++i) {
 442                 extract_token(addrbuf, public_clients, i, '|', sizeof addrbuf);
 443                 if (!strcasecmp(CC->cs_addr, addrbuf)) {
 444                         syslog(LOG_DEBUG, "... yes its local.\n");
 445                         return(1);
 446                 }
 447         }
 448
 449         /* No hits.  This is not a public client. */
 450         syslog(LOG_DEBUG, "... no it isn't.\n");
 451         return(0);
 452 }
 453
 454
 455 /*
 456  * the client is identifying itself to the server
 457  */
 458 void cmd_iden(char *argbuf)
 459 {
 460         int dev_code;
 461         int cli_code;
 462         int rev_level;
 463         char desc[128];
 464         char from_host[128];
 465
 466         if (num_parms(argbuf)<4) {
 467                 cprintf("%d usage error\n", ERROR + ILLEGAL_VALUE);
 468                 return;
 469         }
 470
 471         dev_code = extract_int(argbuf,0);
 472         cli_code = extract_int(argbuf,1);
 473         rev_level = extract_int(argbuf,2);
 474         extract_token(desc, argbuf, 3, '|', sizeof desc);
 475
 476         safestrncpy(from_host, config.c_fqdn, sizeof from_host);
 477         from_host[sizeof from_host - 1] = 0;
 478         if (num_parms(argbuf)>=5) extract_token(from_host, argbuf, 4, '|', sizeof from_host);
 479
 480         CC->cs_clientdev = dev_code;
 481         CC->cs_clienttyp = cli_code;
 482         CC->cs_clientver = rev_level;
 483         safestrncpy(CC->cs_clientname, desc, sizeof CC->cs_clientname);
 484         CC->cs_clientname[31] = 0;
 485
 486         /* For local sockets and public clients, trust the hostname supplied by the client */
 487         if ( (CC->is_local_socket) || (is_public_client()) ) {
 488                 safestrncpy(CC->cs_host, from_host, sizeof CC->cs_host);
 489                 CC->cs_host[sizeof CC->cs_host - 1] = 0;
 490                 CC->cs_addr[0] = 0;
 491         }
 492
 493         syslog(LOG_NOTICE, "Client %d/%d/%01d.%02d (%s) from %s\n",
 494                 dev_code,
 495                 cli_code,
 496                 (rev_level / 100),
 497                 (rev_level % 100),
 498                 desc,
 499                 CC->cs_host
 500         );
 501         cprintf("%d Ok\n",CIT_OK);
 502 }
 503
 504 typedef const char *ccharp;
 505 /*
 506  * display system messages or help
 507  */
 508 void cmd_mesg(char *mname)
 509 {
 510         FILE *mfp;
 511         char targ[256];
 512         char buf[256];
 513         char buf2[256];
 514         char *dirs[2];
 515         DIR *dp;
 516         struct dirent *d;
 517
 518         extract_token(buf, mname, 0, '|', sizeof buf);
 519
 520         dirs[0] = strdup(ctdl_message_dir);
 521         dirs[1] = strdup(ctdl_hlp_dir);
 522
 523         snprintf(buf2, sizeof buf2, "%s.%d.%d",
 524                 buf, CC->cs_clientdev, CC->cs_clienttyp);
 525
 526         /* If the client requested "?" then produce a listing */
 527         if (!strcmp(buf, "?")) {
 528                 cprintf("%d %s\n", LISTING_FOLLOWS, buf);
 529                 dp = opendir(dirs[1]);
 530                 if (dp != NULL) {
 531                         while (d = readdir(dp), d != NULL) {
 532                                 if (d->d_name[0] != '.') {
 533                                         cprintf(" %s\n", d->d_name);
 534                                 }
 535                         }
 536                         closedir(dp);
 537                 }
 538                 cprintf("000\n");
 539                 free(dirs[0]);
 540                 free(dirs[1]);
 541                 return;
 542         }
 543
 544         /* Otherwise, look for the requested file by name. */
 545         else {
 546                 mesg_locate(targ, sizeof targ, buf2, 2, (const ccharp*)dirs);
 547                 if (IsEmptyStr(targ)) {
 548                         snprintf(buf2, sizeof buf2, "%s.%d",
 549                                                         buf, CC->cs_clientdev);
 550                         mesg_locate(targ, sizeof targ, buf2, 2,
 551                                     (const ccharp*)dirs);
 552                         if (IsEmptyStr(targ)) {
 553                                 mesg_locate(targ, sizeof targ, buf, 2,
 554                                             (const ccharp*)dirs);
 555                         }
 556                 }
 557         }
 558
 559         free(dirs[0]);
 560         free(dirs[1]);
 561
 562         if (IsEmptyStr(targ)) {
 563                 cprintf("%d '%s' not found.  (Searching in %s and %s)\n",
 564                         ERROR + FILE_NOT_FOUND,
 565                         mname,
 566                         ctdl_message_dir,
 567                         ctdl_hlp_dir
 568                 );
 569                 return;
 570         }
 571
 572         mfp = fopen(targ, "r");
 573         if (mfp==NULL) {
 574                 cprintf("%d Cannot open '%s': %s\n",
 575                         ERROR + INTERNAL_ERROR, targ, strerror(errno));
 576                 return;
 577         }
 578         cprintf("%d %s\n", LISTING_FOLLOWS,buf);
 579
 580         while (fgets(buf, (sizeof buf - 1), mfp) != NULL) {
 581                 buf[strlen(buf)-1] = 0;
 582                 do_help_subst(buf);
 583                 cprintf("%s\n",buf);
 584         }
 585
 586         fclose(mfp);
 587         cprintf("000\n");
 588 }
 589
 590
 591 /*
 592  * enter system messages or help
 593  */
 594 void cmd_emsg(char *mname)
 595 {
 596         FILE *mfp;
 597         char targ[256];
 598         char buf[256];
 599         char *dirs[2];
 600         int a;
 601
 602         unbuffer_output();
 603
 604         if (CtdlAccessCheck(ac_aide)) return;
 605
 606         extract_token(buf, mname, 0, '|', sizeof buf);
 607         for (a=0; !IsEmptyStr(&buf[a]); ++a) {          /* security measure */
 608                 if (buf[a] == '/') buf[a] = '.';
 609         }
 610
 611         dirs[0] = strdup(ctdl_message_dir);
 612         dirs[1] = strdup(ctdl_hlp_dir);
 613
 614         mesg_locate(targ, sizeof targ, buf, 2, (const ccharp*)dirs);
 615         free(dirs[0]);
 616         free(dirs[1]);
 617
 618         if (IsEmptyStr(targ)) {
 619                 snprintf(targ, sizeof targ,
 620                                  "%s/%s",
 621                                  ctdl_hlp_dir, buf);
 622         }
 623
 624         mfp = fopen(targ,"w");
 625         if (mfp==NULL) {
 626                 cprintf("%d Cannot open '%s': %s\n",
 627                         ERROR + INTERNAL_ERROR, targ, strerror(errno));
 628                 return;
 629         }
 630         cprintf("%d %s\n", SEND_LISTING, targ);
 631
 632         while (client_getln(buf, sizeof buf) >=0 && strcmp(buf, "000")) {
 633                 fprintf(mfp, "%s\n", buf);
 634         }
 635
 636         fclose(mfp);
 637 }
 638
 639
 640 /* Don't show the names of private rooms unless the viewing
 641  * user also knows the rooms.
 642  */
 643 void GenerateRoomDisplay(char *real_room,
 644                         CitContext *viewed,
 645                         CitContext *viewer) {
 646
 647         int ra;
 648
 649         strcpy(real_room, viewed->room.QRname);
 650         if (viewed->room.QRflags & QR_MAILBOX) {
 651                 strcpy(real_room, &real_room[11]);
 652         }
 653         if (viewed->room.QRflags & QR_PRIVATE) {
 654                 CtdlRoomAccess(&viewed->room, &viewer->user, &ra, NULL);
 655                 if ( (ra & UA_KNOWN) == 0) {
 656                         strcpy(real_room, " ");
 657                 }
 658         }
 659
 660         if (viewed->cs_flags & CS_CHAT) {
 661                 while (strlen(real_room) < 14) {
 662                         strcat(real_room, " ");
 663                 }
 664                 strcpy(&real_room[14], "<chat>");
 665         }
 666
 667 }
 668
 669 /*
 670  * Convenience function.
 671  */
 672 int CtdlAccessCheck(int required_level) {
 673
 674         if (CC->internal_pgm) return(0);
 675         if (required_level >= ac_internal) {
 676                 cprintf("%d This is not a user-level command.\n",
 677                         ERROR + HIGHER_ACCESS_REQUIRED);
 678                 return(-1);
 679         }
 680
 681         if ((required_level >= ac_logged_in_or_guest) && (CC->logged_in == 0) && (!config.c_guest_logins)) {
 682                 cprintf("%d Not logged in.\n", ERROR + NOT_LOGGED_IN);
 683                 return(-1);
 684         }
 685
 686         if ((required_level >= ac_logged_in) && (CC->logged_in == 0)) {
 687                 cprintf("%d Not logged in.\n", ERROR + NOT_LOGGED_IN);
 688                 return(-1);
 689         }
 690
 691         if (CC->user.axlevel >= AxAideU) return(0);
 692         if (required_level >= ac_aide) {
 693                 cprintf("%d This command requires Aide access.\n",
 694                         ERROR + HIGHER_ACCESS_REQUIRED);
 695                 return(-1);
 696         }
 697
 698         if (is_room_aide()) return(0);
 699         if (required_level >= ac_room_aide) {
 700                 cprintf("%d This command requires Aide or Room Aide access.\n",
 701                         ERROR + HIGHER_ACCESS_REQUIRED);
 702                 return(-1);
 703         }
 704
 705         /* shhh ... succeed quietly */
 706         return(0);
 707 }
 708
 709
 710
 711 /*
 712  * Terminate another running session
 713  */
 714 void cmd_term(char *cmdbuf)
 715 {
 716         int session_num;
 717         int terminated = 0;
 718
 719         session_num = extract_int(cmdbuf, 0);
 720
 721         terminated = CtdlTerminateOtherSession(session_num);
 722
 723         if (terminated < 0) {
 724                 cprintf("%d You can't kill your own session.\n", ERROR + ILLEGAL_VALUE);
 725                 return;
 726         }
 727
 728         if (terminated & TERM_FOUND) {
 729                 if (terminated == TERM_KILLED) {
 730                         cprintf("%d Session terminated.\n", CIT_OK);
 731                 }
 732                 else {
 733                         cprintf("%d You are not allowed to do that.\n",
 734                                 ERROR + HIGHER_ACCESS_REQUIRED);
 735                 }
 736         }
 737         else {
 738                 cprintf("%d No such session.\n", ERROR + ILLEGAL_VALUE);
 739         }
 740 }
 741
 742
 743 /*
 744  * get the paginator prompt
 745  */
 746 void cmd_more(char *argbuf) {
 747         cprintf("%d %s\n", CIT_OK, config.c_moreprompt);
 748 }
 749
 750
 751 /*
 752  * echo
 753  */
 754 void cmd_echo(char *etext)
 755 {
 756         cprintf("%d %s\n", CIT_OK, etext);
 757 }
 758
 759
 760
 761 /*
 762  * Shut down the server
 763  */
 764 void cmd_down(char *argbuf) {
 765         char *Reply ="%d Shutting down server.  Goodbye.\n";
 766
 767         if (CtdlAccessCheck(ac_aide)) return;
 768
 769         if (!IsEmptyStr(argbuf))
 770         {
 771                 int state = CIT_OK;
 772                 restart_server = extract_int(argbuf, 0);
 773
 774                 if (restart_server > 0)
 775                 {
 776                         Reply = "%d citserver will now shut down and automatically restart.\n";
 777                 }
 778                 if ((restart_server > 0) && !running_as_daemon)
 779                 {
 780                         syslog(LOG_ERR, "The user requested restart, but not running as daemon! Geronimooooooo!\n");
 781                         Reply = "%d Warning: citserver is not running in daemon mode and is therefore unlikely to restart automatically.\n";
 782                         state = ERROR;
 783                 }
 784                 cprintf(Reply, state);
 785         }
 786         else
 787         {
 788                 cprintf(Reply, CIT_OK + SERVER_SHUTTING_DOWN);
 789         }
 790         CC->kill_me = KILLME_SERVER_SHUTTING_DOWN;
 791         server_shutting_down = 1;
 792 }
 793
 794
 795 /*
 796  * Halt the server without exiting the server process.
 797  */
 798 void cmd_halt(char *argbuf) {
 799
 800         if (CtdlAccessCheck(ac_aide)) return;
 801
 802         cprintf("%d Halting server.  Goodbye.\n", CIT_OK);
 803         server_shutting_down = 1;
 804         shutdown_and_halt = 1;
 805 }
 806
 807
 808 /*
 809  * Schedule or cancel a server shutdown
 810  */
 811 void cmd_scdn(char *argbuf)
 812 {
 813         int new_state;
 814         int state = CIT_OK;
 815         char *Reply = "%d %d\n";
 816
 817         if (CtdlAccessCheck(ac_aide)) return;
 818
 819         new_state = extract_int(argbuf, 0);
 820         if ((new_state == 2) || (new_state == 3))
 821         {
 822                 restart_server = 1;
 823                 if (!running_as_daemon)
 824                 {
 825                         syslog(LOG_ERR, "The user requested restart, but not running as deamon! Geronimooooooo!\n");
 826                         Reply = "%d %d Warning, not running in deamon mode. maybe we will come up again, but don't lean on it.\n";
 827                         state = ERROR;
 828                 }
 829
 830                 restart_server = extract_int(argbuf, 0);
 831                 new_state -= 2;
 832         }
 833         if ((new_state == 0) || (new_state == 1)) {
 834                 ScheduledShutdown = new_state;
 835         }
 836         cprintf(Reply, state, ScheduledShutdown);
 837 }
 838
 839
 840 /*
 841  * Set or unset asynchronous protocol mode
 842  */
 843 void cmd_asyn(char *argbuf)
 844 {
 845         int new_state;
 846
 847         new_state = extract_int(argbuf, 0);
 848         if ((new_state == 0) || (new_state == 1)) {
 849                 CC->is_async = new_state;
 850         }
 851         cprintf("%d %d\n", CIT_OK, CC->is_async);
 852 }
 853
 854
 855
 856 /*
 857  * Back-end function for starting a session
 858  */
 859 void begin_session(CitContext *con)
 860 {
 861         /*
 862          * Initialize some variables specific to our context.
 863          */
 864         con->logged_in = 0;
 865         con->internal_pgm = 0;
 866         con->download_fp = NULL;
 867         con->upload_fp = NULL;
 868         con->cached_msglist = NULL;
 869         con->cached_num_msgs = 0;
 870         con->FirstExpressMessage = NULL;
 871         time(&con->lastcmd);
 872         time(&con->lastidle);
 873         strcpy(con->lastcmdname, "    ");
 874         strcpy(con->cs_clientname, "(unknown)");
 875         strcpy(con->curr_user, NLI);
 876         *con->net_node = '\0';
 877         *con->fake_username = '\0';
 878         *con->fake_hostname = '\0';
 879         *con->fake_roomname = '\0';
 880         *con->cs_clientinfo = '\0';
 881         safestrncpy(con->cs_host, config.c_fqdn, sizeof con->cs_host);
 882         safestrncpy(con->cs_addr, "", sizeof con->cs_addr);
 883         con->cs_UDSclientUID = -1;
 884         con->cs_host[sizeof con->cs_host - 1] = 0;
 885         if (!CC->is_local_socket) {
 886                 locate_host(con->cs_host, sizeof con->cs_host,
 887                         con->cs_addr, sizeof con->cs_addr,
 888                         con->client_socket
 889                 );
 890         }
 891         else {
 892                 con->cs_host[0] = 0;
 893                 con->cs_addr[0] = 0;
 894 #ifdef HAVE_STRUCT_UCRED
 895                 {
 896                         /* as http://www.wsinnovations.com/softeng/articles/uds.html told us... */
 897                         struct ucred credentials;
 898                         socklen_t ucred_length = sizeof(struct ucred);
 899
 900                         /*fill in the user data structure */
 901                         if(getsockopt(con->client_socket, SOL_SOCKET, SO_PEERCRED, &credentials, &ucred_length)) {
 902                                 syslog(LOG_NOTICE, "could obtain credentials from unix domain socket");
 903
 904                         }
 905                         else {
 906                                 /* the process ID of the process on the other side of the socket */
 907                                 /* credentials.pid; */
 908
 909                                 /* the effective UID of the process on the other side of the socket  */
 910                                 con->cs_UDSclientUID = credentials.uid;
 911
 912                                 /* the effective primary GID of the process on the other side of the socket */
 913                                 /* credentials.gid; */
 914
 915                                 /* To get supplemental groups, we will have to look them up in our account
 916                                    database, after a reverse lookup on the UID to get the account name.
 917                                    We can take this opportunity to check to see if this is a legit account.
 918                                 */
 919                                 snprintf(con->cs_clientinfo, sizeof(con->cs_clientinfo),
 920                                          "PID: "F_PID_T"; UID: "F_UID_T"; GID: "F_XPID_T" ",
 921                                          credentials.pid,
 922                                          credentials.uid,
 923                                          credentials.gid);
 924                         }
 925                 }
 926 #endif
 927         }
 928         con->cs_flags = 0;
 929         con->upload_type = UPL_FILE;
 930         con->dl_is_net = 0;
 931
 932         con->nologin = 0;
 933         if (((config.c_maxsessions > 0)&&(num_sessions > config.c_maxsessions)) || CtdlWantSingleUser()) {
 934                 con->nologin = 1;
 935         }
 936
 937         if (!CC->is_local_socket) {
 938                 syslog(LOG_NOTICE, "Session (%s) started from %s (%s).\n", con->ServiceName, con->cs_host, con->cs_addr);
 939         }
 940         else {
 941                 syslog(LOG_NOTICE, "Session (%s) started via local socket UID:%d.\n", con->ServiceName, con->cs_UDSclientUID);
 942         }
 943
 944         /* Run any session startup routines registered by loadable modules */
 945         PerformSessionHooks(EVT_START);
 946 }
 947
 948
 949 void citproto_begin_session() {
 950         if (CC->nologin==1) {
 951                 cprintf("%d %s: Too many users are already online (maximum is %d)\n",
 952                         ERROR + MAX_SESSIONS_EXCEEDED,
 953                         config.c_nodename, config.c_maxsessions
 954                 );
 955                 CC->kill_me = KILLME_MAX_SESSIONS_EXCEEDED;
 956         }
 957         else {
 958                 cprintf("%d %s Citadel server ready.\n", CIT_OK, config.c_nodename);
 959                 CC->can_receive_im = 1;
 960         }
 961 }
 962
 963
 964 void citproto_begin_admin_session() {
 965         CC->internal_pgm = 1;
 966         cprintf("%d %s Citadel server ADMIN CONNECTION ready.\n", CIT_OK, config.c_nodename);
 967 }
 968
 969
 970 void cmd_noop(char *argbuf)
 971 {
 972         cprintf("%d%cok\n", CIT_OK, CtdlCheckExpress() );
 973 }
 974
 975
 976 void cmd_qnop(char *argbuf)
 977 {
 978         /* do nothing, this command returns no response */
 979 }
 980
 981
 982 void cmd_quit(char *argbuf)
 983 {
 984         cprintf("%d Goodbye.\n", CIT_OK);
 985         CC->kill_me = KILLME_CLIENT_LOGGED_OUT;
 986 }
 987
 988
 989 void cmd_lout(char *argbuf)
 990 {
 991         if (CC->logged_in)
 992                 CtdlUserLogout();
 993         cprintf("%d logged out.\n", CIT_OK);
 994 }
 995
 996
 997 /*
 998  * This loop recognizes all server commands.
 999  */
1000 void do_command_loop(void) {
1001         char cmdbuf[SIZ];
1002
1003         time(&CC->lastcmd);
1004         memset(cmdbuf, 0, sizeof cmdbuf); /* Clear it, just in case */
1005         if (client_getln(cmdbuf, sizeof cmdbuf) < 1) {
1006                 syslog(LOG_ERR, "Citadel client disconnected: ending session.\n");
1007                 CC->kill_me = KILLME_CLIENT_DISCONNECTED;
1008                 return;
1009         }
1010
1011         /* Log the server command, but don't show passwords... */
1012         if ( (strncasecmp(cmdbuf, "PASS", 4)) && (strncasecmp(cmdbuf, "SETP", 4)) ) {
1013                 syslog(LOG_INFO, "[%d][%s(%ld)] %s",
1014                         CC->cs_pid, CC->curr_user, CC->user.usernum, cmdbuf
1015                 );
1016         }
1017         else {
1018                 syslog(LOG_INFO, "[%d][%s(%ld)] <password command hidden from log>",
1019                         CC->cs_pid, CC->curr_user, CC->user.usernum
1020                 );
1021         }
1022
1023         buffer_output();
1024
1025         /*
1026          * Let other clients see the last command we executed, and
1027          * update the idle time, but not NOOP, QNOP, PEXP, GEXP, RWHO, or TIME.
1028          */
1029         if ( (strncasecmp(cmdbuf, "NOOP", 4))
1030            && (strncasecmp(cmdbuf, "QNOP", 4))
1031            && (strncasecmp(cmdbuf, "PEXP", 4))
1032            && (strncasecmp(cmdbuf, "GEXP", 4))
1033            && (strncasecmp(cmdbuf, "RWHO", 4))
1034            && (strncasecmp(cmdbuf, "TIME", 4)) ) {
1035                 strcpy(CC->lastcmdname, "    ");
1036                 safestrncpy(CC->lastcmdname, cmdbuf, sizeof(CC->lastcmdname));
1037                 time(&CC->lastidle);
1038         }
1039
1040         if ((strncasecmp(cmdbuf, "ENT0", 4))
1041            && (strncasecmp(cmdbuf, "MESG", 4))
1042            && (strncasecmp(cmdbuf, "MSGS", 4)))
1043         {
1044            CC->cs_flags &= ~CS_POSTING;
1045         }
1046
1047         if (!DLoader_Exec_Cmd(cmdbuf)) {
1048                 cprintf("%d Unrecognized or unsupported command.\n", ERROR + CMD_NOT_SUPPORTED);
1049         }
1050
1051         unbuffer_output();
1052
1053         /* Run any after-each-command routines registered by modules */
1054         PerformSessionHooks(EVT_CMD);
1055 }
1056
1057
1058 /*
1059  * This loop performs all asynchronous functions.
1060  */
1061 void do_async_loop(void) {
1062         PerformSessionHooks(EVT_ASYNC);
1063 }
1064
1065
1066 /*****************************************************************************/
1067 /*                      MODULE INITIALIZATION STUFF                          */
1068 /*****************************************************************************/
1069
1070 CTDL_MODULE_INIT(citserver)
1071 {
1072         if (!threading) {
1073                 CtdlRegisterProtoHook(cmd_noop, "NOOP", "no operation");
1074                 CtdlRegisterProtoHook(cmd_qnop, "QNOP", "no operation with no response");
1075                 CtdlRegisterProtoHook(cmd_quit, "QUIT", "log out and disconnect from server");
1076                 CtdlRegisterProtoHook(cmd_lout, "LOUT", "log out but do not disconnect from server");
1077                 CtdlRegisterProtoHook(cmd_asyn, "ASYN", "enable asynchronous server responses");
1078                 CtdlRegisterProtoHook(cmd_info, "INFO", "fetch server capabilities and configuration");
1079                 CtdlRegisterProtoHook(cmd_mesg, "MESG", "fetch system banners");
1080                 CtdlRegisterProtoHook(cmd_emsg, "EMSG", "submit system banners");
1081                 CtdlRegisterProtoHook(cmd_echo, "ECHO", "echo text back to the client");
1082                 CtdlRegisterProtoHook(cmd_more, "MORE", "fetch the paginator prompt");
1083                 CtdlRegisterProtoHook(cmd_iden, "IDEN", "identify the client software and location");
1084                 CtdlRegisterProtoHook(cmd_term, "TERM", "terminate another running session");
1085                 CtdlRegisterProtoHook(cmd_down, "DOWN", "perform a server shutdown");
1086                 CtdlRegisterProtoHook(cmd_halt, "HALT", "halt the server without exiting the server process");
1087                 CtdlRegisterProtoHook(cmd_scdn, "SCDN", "schedule or cancel a server shutdown");
1088                 CtdlRegisterProtoHook(cmd_time, "TIME", "fetch the date and time from the server");
1089         }
1090         /* return our id for the Log */
1091         return "citserver";
1092 }