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
 173         syslog(LOG_INFO, "Opening databases\n");
 174         open_databases();
 175
 176         ctdl_thread_internal_init_tsd();
 177
 178         CtdlThreadAllocTSD();
 179
 180         check_ref_counts();
 181
 182         syslog(LOG_INFO, "Creating base rooms (if necessary)\n");
 183         CtdlCreateRoom(config.c_baseroom,       0, "", 0, 1, 0, VIEW_BBS);
 184         CtdlCreateRoom(AIDEROOM,                3, "", 0, 1, 0, VIEW_BBS);
 185         CtdlCreateRoom(SYSCONFIGROOM,           3, "", 0, 1, 0, VIEW_BBS);
 186         CtdlCreateRoom(config.c_twitroom,       0, "", 0, 1, 0, VIEW_BBS);
 187
 188         /* The "Local System Configuration" room doesn't need to be visible */
 189         if (CtdlGetRoomLock(&qrbuf, SYSCONFIGROOM) == 0) {
 190                 qrbuf.QRflags2 |= QR2_SYSTEM;
 191                 CtdlPutRoomLock(&qrbuf);
 192         }
 193
 194         /* Aide needs to be public postable, else we're not RFC conformant. */
 195         if (CtdlGetRoomLock(&qrbuf, AIDEROOM) == 0) {
 196                 qrbuf.QRflags2 |= QR2_SMTP_PUBLIC;
 197                 CtdlPutRoomLock(&qrbuf);
 198         }
 199
 200         syslog(LOG_INFO, "Seeding the pseudo-random number generator...\n");
 201         urandom = fopen("/dev/urandom", "r");
 202         if (urandom != NULL) {
 203                 rv = fread(&seed, sizeof seed, 1, urandom);
 204                 fclose(urandom);
 205         }
 206         else {
 207                 gettimeofday(&tv, NULL);
 208                 seed = tv.tv_usec;
 209         }
 210         srand(seed);
 211         srandom(seed);
 212
 213         syslog(LOG_INFO, "Initializing ipgm secret\n");
 214         get_config();
 215         config.c_ipgm_secret = rand();
 216         put_config();
 217
 218         syslog(LOG_DEBUG, "master_startup() finished\n");
 219 }
 220
 221
 222 /*
 223  * Cleanup routine to be called when the server is shutting down.
 224  */
 225 void master_cleanup(int exitcode) {
 226         struct CleanupFunctionHook *fcn;
 227         static int already_cleaning_up = 0;
 228
 229         if (already_cleaning_up) while(1) sleep(1);
 230         already_cleaning_up = 1;
 231
 232         /* Run any cleanup routines registered by loadable modules */
 233         for (fcn = CleanupHookTable; fcn != NULL; fcn = fcn->next) {
 234                 (*fcn->h_function_pointer)();
 235         }
 236
 237         /* Close the AdjRefCount queue file */
 238         AdjRefCount(-1, 0);
 239
 240         /* Do system-dependent stuff */
 241         sysdep_master_cleanup();
 242
 243         /* Close databases */
 244         syslog(LOG_INFO, "Closing databases\n");
 245         close_databases();
 246
 247 #ifdef DEBUG_MEMORY_LEAKS
 248         dump_heap();
 249 #endif
 250
 251         /* If the operator requested a halt but not an exit, halt here. */
 252         if (shutdown_and_halt) {
 253                 syslog(LOG_NOTICE, "citserver: Halting server without exiting.\n");
 254                 fflush(stdout); fflush(stderr);
 255                 while(1) {
 256                         sleep(32767);
 257                 }
 258         }
 259
 260         release_control();
 261
 262         /* Now go away. */
 263         syslog(LOG_NOTICE, "citserver: Exiting with status %d\n", exitcode);
 264         fflush(stdout); fflush(stderr);
 265
 266         if (restart_server != 0)
 267                 exit(1);
 268         if ((running_as_daemon != 0) && ((exitcode == 0) ))
 269                 exitcode = CTDLEXIT_SHUTDOWN;
 270         exit(exitcode);
 271 }
 272
 273
 274
 275 /*
 276  * cmd_info()  -  tell the client about this server
 277  */
 278 void cmd_info(char *cmdbuf) {
 279         cprintf("%d Server info:\n", LISTING_FOLLOWS);
 280         cprintf("%d\n", CC->cs_pid);
 281         cprintf("%s\n", config.c_nodename);
 282         cprintf("%s\n", config.c_humannode);
 283         cprintf("%s\n", config.c_fqdn);
 284         cprintf("%s\n", CITADEL);
 285         cprintf("%d\n", REV_LEVEL);
 286         cprintf("%s\n", config.c_site_location);
 287         cprintf("%s\n", config.c_sysadm);
 288         cprintf("%d\n", SERVER_TYPE);
 289         cprintf("%s\n", config.c_moreprompt);
 290         cprintf("1\n"); /* 1 = yes, this system supports floors */
 291         cprintf("1\n"); /* 1 = we support the extended paging options */
 292         cprintf("\n");  /* nonce no longer supported */
 293         cprintf("1\n"); /* 1 = yes, this system supports the QNOP command */
 294
 295 #ifdef HAVE_LDAP
 296         cprintf("1\n"); /* 1 = yes, this server is LDAP-enabled */
 297 #else
 298         cprintf("0\n"); /* 1 = no, this server is not LDAP-enabled */
 299 #endif
 300
 301         if (config.c_auth_mode == AUTHMODE_NATIVE) {
 302                 cprintf("%d\n", config.c_disable_newu);
 303         }
 304         else {
 305                 cprintf("1\n"); /* "create new user" does not work with non-native auth modes */
 306         }
 307
 308         cprintf("%s\n", config.c_default_cal_zone);
 309
 310         /* Output load averages */
 311         cprintf("%f\n", CtdlThreadLoadAvg);
 312         cprintf("%f\n", CtdlThreadWorkerAvg);
 313         cprintf("%d\n", CtdlThreadGetCount());
 314
 315         cprintf("1\n");         /* yes, Sieve mail filtering is supported */
 316         cprintf("%d\n", config.c_enable_fulltext);
 317         cprintf("%s\n", svn_revision());
 318
 319         if (config.c_auth_mode == AUTHMODE_NATIVE) {
 320                 cprintf("%d\n", openid_level_supported); /* OpenID is enabled when using native auth */
 321         }
 322         else {
 323                 cprintf("0\n"); /* OpenID is disabled when using non-native auth */
 324         }
 325
 326         cprintf("%d\n", config.c_guest_logins);
 327
 328         cprintf("000\n");
 329 }
 330
 331
 332 /*
 333  * returns an asterisk if there are any instant messages waiting,
 334  * space otherwise.
 335  */
 336 char CtdlCheckExpress(void) {
 337         if (CC->FirstExpressMessage == NULL) {
 338                 return(' ');
 339         }
 340         else {
 341                 return('*');
 342         }
 343 }
 344
 345 void cmd_time(char *argbuf)
 346 {
 347    time_t tv;
 348    struct tm tmp;
 349
 350    tv = time(NULL);
 351    localtime_r(&tv, &tmp);
 352
 353    /* timezone and daylight global variables are not portable. */
 354 #ifdef HAVE_STRUCT_TM_TM_GMTOFF
 355    cprintf("%d %ld|%ld|%d\n", CIT_OK, (long)tv, tmp.tm_gmtoff, tmp.tm_isdst);
 356 #else
 357    cprintf("%d %ld|%ld|%d\n", CIT_OK, (long)tv, timezone, tmp.tm_isdst);
 358 #endif
 359 }
 360
 361
 362 /*
 363  * Check originating host against the public_clients file.  This determines
 364  * whether the client is allowed to change the hostname for this session
 365  * (for example, to show the location of the user rather than the location
 366  * of the client).
 367  */
 368 int is_public_client(void)
 369 {
 370         char buf[1024];
 371         char addrbuf[1024];
 372         FILE *fp;
 373         int i;
 374         char *public_clientspos;
 375         char *public_clientsend;
 376         char *paddr = NULL;
 377         struct stat statbuf;
 378         static time_t pc_timestamp = 0;
 379         static char public_clients[SIZ];
 380         static char public_clients_file[SIZ];
 381
 382 #define LOCALHOSTSTR "127.0.0.1"
 383
 384         snprintf(public_clients_file, sizeof public_clients_file, "%s/public_clients", ctdl_etc_dir);
 385
 386         /*
 387          * Check the time stamp on the public_clients file.  If it's been
 388          * updated since the last time we were here (or if this is the first
 389          * time we've been through the loop), read its contents and learn
 390          * the IP addresses of the listed hosts.
 391          */
 392         if (stat(public_clients_file, &statbuf) != 0) {
 393                 /* No public_clients file exists, so bail out */
 394                 syslog(LOG_WARNING, "Warning: '%s' does not exist\n",
 395                                 public_clients_file);
 396                 return(0);
 397         }
 398
 399         if (statbuf.st_mtime > pc_timestamp) {
 400                 begin_critical_section(S_PUBLIC_CLIENTS);
 401                 syslog(LOG_INFO, "Loading %s\n", public_clients_file);
 402
 403                 public_clientspos = &public_clients[0];
 404                 public_clientsend = public_clientspos + SIZ;
 405                 safestrncpy(public_clientspos, LOCALHOSTSTR, sizeof public_clients);
 406                 public_clientspos += sizeof(LOCALHOSTSTR) - 1;
 407
 408                 if (hostname_to_dotted_quad(addrbuf, config.c_fqdn) == 0) {
 409                         *(public_clientspos++) = '|';
 410                         paddr = &addrbuf[0];
 411                         while (!IsEmptyStr (paddr) &&
 412                                (public_clientspos < public_clientsend))
 413                                 *(public_clientspos++) = *(paddr++);
 414                 }
 415
 416                 fp = fopen(public_clients_file, "r");
 417                 if (fp != NULL)
 418                         while ((fgets(buf, sizeof buf, fp)!=NULL) &&
 419                                (public_clientspos < public_clientsend)){
 420                                 char *ptr;
 421                                 ptr = buf;
 422                                 while (!IsEmptyStr(ptr)) {
 423                                         if (*ptr == '#') {
 424                                                 *ptr = 0;
 425                                                 break;
 426                                         }
 427                                 else ptr++;
 428                                 }
 429                                 ptr--;
 430                                 while (ptr>buf && isspace(*ptr)) {
 431                                         *(ptr--) = 0;
 432                                 }
 433                                 if (hostname_to_dotted_quad(addrbuf, buf) == 0) {
 434                                         *(public_clientspos++) = '|';
 435                                         paddr = addrbuf;
 436                                         while (!IsEmptyStr(paddr) &&
 437                                                (public_clientspos < public_clientsend)){
 438                                                 *(public_clientspos++) = *(paddr++);
 439                                         }
 440                                 }
 441                         }
 442                 fclose(fp);
 443                 pc_timestamp = time(NULL);
 444                 end_critical_section(S_PUBLIC_CLIENTS);
 445         }
 446
 447         syslog(LOG_DEBUG, "Checking whether %s is a local or public client\n",
 448                 CC->cs_addr);
 449         for (i=0; i<num_parms(public_clients); ++i) {
 450                 extract_token(addrbuf, public_clients, i, '|', sizeof addrbuf);
 451                 if (!strcasecmp(CC->cs_addr, addrbuf)) {
 452                         syslog(LOG_DEBUG, "... yes it is.\n");
 453                         return(1);
 454                 }
 455         }
 456
 457         /* No hits.  This is not a public client. */
 458         syslog(LOG_DEBUG, "... no it isn't.\n");
 459         return(0);
 460 }
 461
 462
 463 /*
 464  * the client is identifying itself to the server
 465  */
 466 void cmd_iden(char *argbuf)
 467 {
 468         int dev_code;
 469         int cli_code;
 470         int rev_level;
 471         char desc[128];
 472         char from_host[128];
 473
 474         if (num_parms(argbuf)<4) {
 475                 cprintf("%d usage error\n", ERROR + ILLEGAL_VALUE);
 476                 return;
 477         }
 478
 479         dev_code = extract_int(argbuf,0);
 480         cli_code = extract_int(argbuf,1);
 481         rev_level = extract_int(argbuf,2);
 482         extract_token(desc, argbuf, 3, '|', sizeof desc);
 483
 484         safestrncpy(from_host, config.c_fqdn, sizeof from_host);
 485         from_host[sizeof from_host - 1] = 0;
 486         if (num_parms(argbuf)>=5) extract_token(from_host, argbuf, 4, '|', sizeof from_host);
 487
 488         CC->cs_clientdev = dev_code;
 489         CC->cs_clienttyp = cli_code;
 490         CC->cs_clientver = rev_level;
 491         safestrncpy(CC->cs_clientname, desc, sizeof CC->cs_clientname);
 492         CC->cs_clientname[31] = 0;
 493
 494         /* For local sockets and public clients, trust the hostname supplied by the client */
 495         if ( (CC->is_local_socket) || (is_public_client()) ) {
 496                 safestrncpy(CC->cs_host, from_host, sizeof CC->cs_host);
 497                 CC->cs_host[sizeof CC->cs_host - 1] = 0;
 498                 CC->cs_addr[0] = 0;
 499         }
 500
 501         syslog(LOG_NOTICE, "Client %d/%d/%01d.%02d (%s) from %s\n",
 502                 dev_code,
 503                 cli_code,
 504                 (rev_level / 100),
 505                 (rev_level % 100),
 506                 desc,
 507                 CC->cs_host
 508         );
 509         cprintf("%d Ok\n",CIT_OK);
 510 }
 511
 512 typedef const char *ccharp;
 513 /*
 514  * display system messages or help
 515  */
 516 void cmd_mesg(char *mname)
 517 {
 518         FILE *mfp;
 519         char targ[256];
 520         char buf[256];
 521         char buf2[256];
 522         char *dirs[2];
 523         DIR *dp;
 524         struct dirent *d;
 525
 526         extract_token(buf, mname, 0, '|', sizeof buf);
 527
 528         dirs[0] = strdup(ctdl_message_dir);
 529         dirs[1] = strdup(ctdl_hlp_dir);
 530
 531         snprintf(buf2, sizeof buf2, "%s.%d.%d",
 532                 buf, CC->cs_clientdev, CC->cs_clienttyp);
 533
 534         /* If the client requested "?" then produce a listing */
 535         if (!strcmp(buf, "?")) {
 536                 cprintf("%d %s\n", LISTING_FOLLOWS, buf);
 537                 dp = opendir(dirs[1]);
 538                 if (dp != NULL) {
 539                         while (d = readdir(dp), d != NULL) {
 540                                 if (d->d_name[0] != '.') {
 541                                         cprintf(" %s\n", d->d_name);
 542                                 }
 543                         }
 544                         closedir(dp);
 545                 }
 546                 cprintf("000\n");
 547                 free(dirs[0]);
 548                 free(dirs[1]);
 549                 return;
 550         }
 551
 552         /* Otherwise, look for the requested file by name. */
 553         else {
 554                 mesg_locate(targ, sizeof targ, buf2, 2, (const ccharp*)dirs);
 555                 if (IsEmptyStr(targ)) {
 556                         snprintf(buf2, sizeof buf2, "%s.%d",
 557                                                         buf, CC->cs_clientdev);
 558                         mesg_locate(targ, sizeof targ, buf2, 2,
 559                                     (const ccharp*)dirs);
 560                         if (IsEmptyStr(targ)) {
 561                                 mesg_locate(targ, sizeof targ, buf, 2,
 562                                             (const ccharp*)dirs);
 563                         }
 564                 }
 565         }
 566
 567         free(dirs[0]);
 568         free(dirs[1]);
 569
 570         if (IsEmptyStr(targ)) {
 571                 cprintf("%d '%s' not found.  (Searching in %s and %s)\n",
 572                         ERROR + FILE_NOT_FOUND,
 573                         mname,
 574                         ctdl_message_dir,
 575                         ctdl_hlp_dir
 576                 );
 577                 return;
 578         }
 579
 580         mfp = fopen(targ, "r");
 581         if (mfp==NULL) {
 582                 cprintf("%d Cannot open '%s': %s\n",
 583                         ERROR + INTERNAL_ERROR, targ, strerror(errno));
 584                 return;
 585         }
 586         cprintf("%d %s\n", LISTING_FOLLOWS,buf);
 587
 588         while (fgets(buf, (sizeof buf - 1), mfp) != NULL) {
 589                 buf[strlen(buf)-1] = 0;
 590                 do_help_subst(buf);
 591                 cprintf("%s\n",buf);
 592         }
 593
 594         fclose(mfp);
 595         cprintf("000\n");
 596 }
 597
 598
 599 /*
 600  * enter system messages or help
 601  */
 602 void cmd_emsg(char *mname)
 603 {
 604         FILE *mfp;
 605         char targ[256];
 606         char buf[256];
 607         char *dirs[2];
 608         int a;
 609
 610         unbuffer_output();
 611
 612         if (CtdlAccessCheck(ac_aide)) return;
 613
 614         extract_token(buf, mname, 0, '|', sizeof buf);
 615         for (a=0; !IsEmptyStr(&buf[a]); ++a) {          /* security measure */
 616                 if (buf[a] == '/') buf[a] = '.';
 617         }
 618
 619         dirs[0] = strdup(ctdl_message_dir);
 620         dirs[1] = strdup(ctdl_hlp_dir);
 621
 622         mesg_locate(targ, sizeof targ, buf, 2, (const ccharp*)dirs);
 623         free(dirs[0]);
 624         free(dirs[1]);
 625
 626         if (IsEmptyStr(targ)) {
 627                 snprintf(targ, sizeof targ,
 628                                  "%s/%s",
 629                                  ctdl_hlp_dir, buf);
 630         }
 631
 632         mfp = fopen(targ,"w");
 633         if (mfp==NULL) {
 634                 cprintf("%d Cannot open '%s': %s\n",
 635                         ERROR + INTERNAL_ERROR, targ, strerror(errno));
 636                 return;
 637         }
 638         cprintf("%d %s\n", SEND_LISTING, targ);
 639
 640         while (client_getln(buf, sizeof buf) >=0 && strcmp(buf, "000")) {
 641                 fprintf(mfp, "%s\n", buf);
 642         }
 643
 644         fclose(mfp);
 645 }
 646
 647
 648 /* Don't show the names of private rooms unless the viewing
 649  * user also knows the rooms.
 650  */
 651 void GenerateRoomDisplay(char *real_room,
 652                         CitContext *viewed,
 653                         CitContext *viewer) {
 654
 655         int ra;
 656
 657         strcpy(real_room, viewed->room.QRname);
 658         if (viewed->room.QRflags & QR_MAILBOX) {
 659                 strcpy(real_room, &real_room[11]);
 660         }
 661         if (viewed->room.QRflags & QR_PRIVATE) {
 662                 CtdlRoomAccess(&viewed->room, &viewer->user, &ra, NULL);
 663                 if ( (ra & UA_KNOWN) == 0) {
 664                         strcpy(real_room, "<private room>");
 665                 }
 666         }
 667
 668         if (viewed->cs_flags & CS_CHAT) {
 669                 while (strlen(real_room) < 14) {
 670                         strcat(real_room, " ");
 671                 }
 672                 strcpy(&real_room[14], "<chat>");
 673         }
 674
 675 }
 676
 677 /*
 678  * Convenience function.
 679  */
 680 int CtdlAccessCheck(int required_level) {
 681
 682         if (CC->internal_pgm) return(0);
 683         if (required_level >= ac_internal) {
 684                 cprintf("%d This is not a user-level command.\n",
 685                         ERROR + HIGHER_ACCESS_REQUIRED);
 686                 return(-1);
 687         }
 688
 689         if ((required_level >= ac_logged_in_or_guest) && (CC->logged_in == 0) && (!config.c_guest_logins)) {
 690                 cprintf("%d Not logged in.\n", ERROR + NOT_LOGGED_IN);
 691                 return(-1);
 692         }
 693
 694         if ((required_level >= ac_logged_in) && (CC->logged_in == 0)) {
 695                 cprintf("%d Not logged in.\n", ERROR + NOT_LOGGED_IN);
 696                 return(-1);
 697         }
 698
 699         if (CC->user.axlevel >= AxAideU) return(0);
 700         if (required_level >= ac_aide) {
 701                 cprintf("%d This command requires Aide access.\n",
 702                         ERROR + HIGHER_ACCESS_REQUIRED);
 703                 return(-1);
 704         }
 705
 706         if (is_room_aide()) return(0);
 707         if (required_level >= ac_room_aide) {
 708                 cprintf("%d This command requires Aide or Room Aide access.\n",
 709                         ERROR + HIGHER_ACCESS_REQUIRED);
 710                 return(-1);
 711         }
 712
 713         /* shhh ... succeed quietly */
 714         return(0);
 715 }
 716
 717
 718
 719 /*
 720  * Terminate another running session
 721  */
 722 void cmd_term(char *cmdbuf)
 723 {
 724         int session_num;
 725         int terminated = 0;
 726
 727         session_num = extract_int(cmdbuf, 0);
 728
 729         terminated = CtdlTerminateOtherSession(session_num);
 730
 731         if (terminated < 0) {
 732                 cprintf("%d You can't kill your own session.\n", ERROR + ILLEGAL_VALUE);
 733                 return;
 734         }
 735
 736         if (terminated & TERM_FOUND) {
 737                 if (terminated == TERM_KILLED) {
 738                         cprintf("%d Session terminated.\n", CIT_OK);
 739                 }
 740                 else {
 741                         cprintf("%d You are not allowed to do that.\n",
 742                                 ERROR + HIGHER_ACCESS_REQUIRED);
 743                 }
 744         }
 745         else {
 746                 cprintf("%d No such session.\n", ERROR + ILLEGAL_VALUE);
 747         }
 748 }
 749
 750
 751 /*
 752  * get the paginator prompt
 753  */
 754 void cmd_more(char *argbuf) {
 755         cprintf("%d %s\n", CIT_OK, config.c_moreprompt);
 756 }
 757
 758
 759 /*
 760  * echo
 761  */
 762 void cmd_echo(char *etext)
 763 {
 764         cprintf("%d %s\n", CIT_OK, etext);
 765 }
 766
 767
 768 /*
 769  * Perform privilege escalation for an internal program
 770  */
 771 void cmd_ipgm(char *argbuf)
 772 {
 773         int secret;
 774
 775         secret = extract_int(argbuf, 0);
 776
 777         /* For security reasons, we do NOT allow this command to run
 778          * over the network.  Local sockets only.
 779          */
 780         if (!CC->is_local_socket) {
 781                 sleep(5);
 782                 cprintf("%d Authentication failed.\n", ERROR + PASSWORD_REQUIRED);
 783         }
 784         else if (secret == config.c_ipgm_secret) {
 785                 CC->internal_pgm = 1;
 786                 strcpy(CC->curr_user, "<internal program>");
 787                 CC->cs_flags = CC->cs_flags|CS_STEALTH;
 788                 cprintf("%d Authenticated as an internal program.\n", CIT_OK);
 789         }
 790         else {
 791                 sleep(5);
 792                 cprintf("%d Authentication failed.\n", ERROR + PASSWORD_REQUIRED);
 793                 syslog(LOG_ERR, "Warning: ipgm authentication failed.\n");
 794                 CC->kill_me = 1;
 795         }
 796 }
 797
 798
 799 /*
 800  * Shut down the server
 801  */
 802 void cmd_down(char *argbuf) {
 803         char *Reply ="%d Shutting down server.  Goodbye.\n";
 804
 805         if (CtdlAccessCheck(ac_aide)) return;
 806
 807         if (!IsEmptyStr(argbuf))
 808         {
 809                 int state = CIT_OK;
 810                 restart_server = extract_int(argbuf, 0);
 811
 812                 if (restart_server > 0)
 813                 {
 814                         Reply = "%d citserver will now shut down and automatically restart.\n";
 815                 }
 816                 if ((restart_server > 0) && !running_as_daemon)
 817                 {
 818                         syslog(LOG_ERR, "The user requested restart, but not running as daemon! Geronimooooooo!\n");
 819                         Reply = "%d Warning: citserver is not running in daemon mode and is therefore unlikely to restart automatically.\n";
 820                         state = ERROR;
 821                 }
 822                 cprintf(Reply, state);
 823         }
 824         else
 825         {
 826                 cprintf(Reply, CIT_OK + SERVER_SHUTTING_DOWN);
 827         }
 828         CC->kill_me = 1; /* Even the DOWN command has to follow correct proceedure when disconecting */
 829         CtdlThreadStopAll();
 830 }
 831
 832
 833 /*
 834  * Halt the server without exiting the server process.
 835  */
 836 void cmd_halt(char *argbuf) {
 837
 838         if (CtdlAccessCheck(ac_aide)) return;
 839
 840         cprintf("%d Halting server.  Goodbye.\n", CIT_OK);
 841         CtdlThreadStopAll();
 842         shutdown_and_halt = 1;
 843 }
 844
 845
 846 /*
 847  * Schedule or cancel a server shutdown
 848  */
 849 void cmd_scdn(char *argbuf)
 850 {
 851         int new_state;
 852         int state = CIT_OK;
 853         char *Reply = "%d %d\n";
 854
 855         if (CtdlAccessCheck(ac_aide)) return;
 856
 857         new_state = extract_int(argbuf, 0);
 858         if ((new_state == 2) || (new_state == 3))
 859         {
 860                 restart_server = 1;
 861                 if (!running_as_daemon)
 862                 {
 863                         syslog(LOG_ERR, "The user requested restart, but not running as deamon! Geronimooooooo!\n");
 864                         Reply = "%d %d Warning, not running in deamon mode. maybe we will come up again, but don't lean on it.\n";
 865                         state = ERROR;
 866                 }
 867
 868                 restart_server = extract_int(argbuf, 0);
 869                 new_state -= 2;
 870         }
 871         if ((new_state == 0) || (new_state == 1)) {
 872                 ScheduledShutdown = new_state;
 873         }
 874         cprintf(Reply, state, ScheduledShutdown);
 875 }
 876
 877
 878 /*
 879  * Set or unset asynchronous protocol mode
 880  */
 881 void cmd_asyn(char *argbuf)
 882 {
 883         int new_state;
 884
 885         new_state = extract_int(argbuf, 0);
 886         if ((new_state == 0) || (new_state == 1)) {
 887                 CC->is_async = new_state;
 888         }
 889         cprintf("%d %d\n", CIT_OK, CC->is_async);
 890 }
 891
 892
 893
 894 /*
 895  * Back-end function for starting a session
 896  */
 897 void begin_session(CitContext *con)
 898 {
 899         socklen_t len;
 900         struct sockaddr_in sin;
 901
 902         /*
 903          * Initialize some variables specific to our context.
 904          */
 905         con->logged_in = 0;
 906         con->internal_pgm = 0;
 907         con->download_fp = NULL;
 908         con->upload_fp = NULL;
 909         con->cached_msglist = NULL;
 910         con->cached_num_msgs = 0;
 911         con->FirstExpressMessage = NULL;
 912         time(&con->lastcmd);
 913         time(&con->lastidle);
 914         strcpy(con->lastcmdname, "    ");
 915         strcpy(con->cs_clientname, "(unknown)");
 916         strcpy(con->curr_user, NLI);
 917         *con->net_node = '\0';
 918         *con->fake_username = '\0';
 919         *con->fake_hostname = '\0';
 920         *con->fake_roomname = '\0';
 921         *con->cs_clientinfo = '\0';
 922         safestrncpy(con->cs_host, config.c_fqdn, sizeof con->cs_host);
 923         safestrncpy(con->cs_addr, "", sizeof con->cs_addr);
 924         con->cs_UDSclientUID = -1;
 925         con->cs_host[sizeof con->cs_host - 1] = 0;
 926         len = sizeof sin;
 927         if (!CC->is_local_socket) {
 928                 locate_host(con->cs_host, sizeof con->cs_host,
 929                         con->cs_addr, sizeof con->cs_addr,
 930                         con->client_socket
 931                 );
 932         }
 933         else {
 934                 con->cs_host[0] = 0;
 935                 con->cs_addr[0] = 0;
 936 #ifdef HAVE_STRUCT_UCRED
 937                 {
 938                         /* as http://www.wsinnovations.com/softeng/articles/uds.html told us... */
 939                         struct ucred credentials;
 940                         socklen_t ucred_length = sizeof(struct ucred);
 941
 942                         /*fill in the user data structure */
 943                         if(getsockopt(con->client_socket, SOL_SOCKET, SO_PEERCRED, &credentials, &ucred_length)) {
 944                                 syslog(LOG_NOTICE, "could obtain credentials from unix domain socket");
 945
 946                         }
 947                         else {
 948                                 /* the process ID of the process on the other side of the socket */
 949                                 /* credentials.pid; */
 950
 951                                 /* the effective UID of the process on the other side of the socket  */
 952                                 con->cs_UDSclientUID = credentials.uid;
 953
 954                                 /* the effective primary GID of the process on the other side of the socket */
 955                                 /* credentials.gid; */
 956
 957                                 /* To get supplemental groups, we will have to look them up in our account
 958                                    database, after a reverse lookup on the UID to get the account name.
 959                                    We can take this opportunity to check to see if this is a legit account.
 960                                 */
 961                                 snprintf(con->cs_clientinfo, sizeof(con->cs_clientinfo),
 962                                          "PID: "F_PID_T"; UID: "F_UID_T"; GID: "F_XPID_T" ",
 963                                          credentials.pid,
 964                                          credentials.uid,
 965                                          credentials.gid);
 966                         }
 967                 }
 968 #endif
 969         }
 970         con->cs_flags = 0;
 971         con->upload_type = UPL_FILE;
 972         con->dl_is_net = 0;
 973
 974         con->nologin = 0;
 975         if (((config.c_maxsessions > 0)&&(num_sessions > config.c_maxsessions)) || CtdlWantSingleUser()) {
 976                 con->nologin = 1;
 977         }
 978
 979         if (!CC->is_local_socket) {
 980                 syslog(LOG_NOTICE, "Session (%s) started from %s (%s).\n", con->ServiceName, con->cs_host, con->cs_addr);
 981         }
 982         else {
 983                 syslog(LOG_NOTICE, "Session (%s) started via local socket UID:%d.\n", con->ServiceName, con->cs_UDSclientUID);
 984         }
 985
 986         /* Run any session startup routines registered by loadable modules */
 987         PerformSessionHooks(EVT_START);
 988 }
 989
 990
 991 void citproto_begin_session() {
 992         if (CC->nologin==1) {
 993                 cprintf("%d %s: Too many users are already online (maximum is %d)\n",
 994                         ERROR + MAX_SESSIONS_EXCEEDED,
 995                         config.c_nodename, config.c_maxsessions
 996                 );
 997                 CC->kill_me = 1;
 998         }
 999         else {
1000                 cprintf("%d %s Citadel server ready.\n", CIT_OK, config.c_nodename);
1001                 CC->can_receive_im = 1;
1002         }
1003 }
1004
1005
1006 void cmd_noop(char *argbuf)
1007 {
1008         cprintf("%d%cok\n", CIT_OK, CtdlCheckExpress() );
1009 }
1010
1011
1012 void cmd_qnop(char *argbuf)
1013 {
1014         /* do nothing, this command returns no response */
1015 }
1016
1017
1018 void cmd_quit(char *argbuf)
1019 {
1020         cprintf("%d Goodbye.\n", CIT_OK);
1021         CC->kill_me = 1;
1022 }
1023
1024
1025 void cmd_lout(char *argbuf)
1026 {
1027         if (CC->logged_in)
1028                 CtdlUserLogout();
1029         cprintf("%d logged out.\n", CIT_OK);
1030 }
1031
1032
1033 /*
1034  * This loop recognizes all server commands.
1035  */
1036 void do_command_loop(void) {
1037         char cmdbuf[SIZ];
1038         const char *old_name = NULL;
1039
1040         old_name = CtdlThreadName("do_command_loop");
1041
1042         time(&CC->lastcmd);
1043         memset(cmdbuf, 0, sizeof cmdbuf); /* Clear it, just in case */
1044         if (client_getln(cmdbuf, sizeof cmdbuf) < 1) {
1045                 syslog(LOG_ERR, "Client disconnected: ending session.\n");
1046                 CC->kill_me = 1;
1047                 CtdlThreadName(old_name);
1048                 return;
1049         }
1050
1051         /* Log the server command, but don't show passwords... */
1052         if ( (strncasecmp(cmdbuf, "PASS", 4)) && (strncasecmp(cmdbuf, "SETP", 4)) ) {
1053                 syslog(LOG_INFO, "CtdlCommand [%s] [%s] %s\n", CTDLUSERIP, CC->curr_user, cmdbuf);
1054         }
1055         else {
1056                 syslog(LOG_INFO, "CtdlCommand [%s] [%s] <password command hidden from log>\n", CTDLUSERIP, CC->curr_user);
1057         }
1058
1059         buffer_output();
1060
1061         /*
1062          * Let other clients see the last command we executed, and
1063          * update the idle time, but not NOOP, QNOP, PEXP, GEXP, RWHO, or TIME.
1064          */
1065         if ( (strncasecmp(cmdbuf, "NOOP", 4))
1066            && (strncasecmp(cmdbuf, "QNOP", 4))
1067            && (strncasecmp(cmdbuf, "PEXP", 4))
1068            && (strncasecmp(cmdbuf, "GEXP", 4))
1069            && (strncasecmp(cmdbuf, "RWHO", 4))
1070            && (strncasecmp(cmdbuf, "TIME", 4)) ) {
1071                 strcpy(CC->lastcmdname, "    ");
1072                 safestrncpy(CC->lastcmdname, cmdbuf, sizeof(CC->lastcmdname));
1073                 time(&CC->lastidle);
1074         }
1075
1076         CtdlThreadName(cmdbuf);
1077
1078         if ((strncasecmp(cmdbuf, "ENT0", 4))
1079            && (strncasecmp(cmdbuf, "MESG", 4))
1080            && (strncasecmp(cmdbuf, "MSGS", 4)))
1081         {
1082            CC->cs_flags &= ~CS_POSTING;
1083         }
1084
1085         if (!DLoader_Exec_Cmd(cmdbuf)) {
1086                 cprintf("%d Unrecognized or unsupported command.\n", ERROR + CMD_NOT_SUPPORTED);
1087         }
1088
1089         unbuffer_output();
1090
1091         /* Run any after-each-command routines registered by modules */
1092         PerformSessionHooks(EVT_CMD);
1093         CtdlThreadName(old_name);
1094 }
1095
1096
1097 /*
1098  * This loop performs all asynchronous functions.
1099  */
1100 void do_async_loop(void) {
1101         PerformSessionHooks(EVT_ASYNC);
1102 }
1103
1104
1105 /*****************************************************************************/
1106 /*                      MODULE INITIALIZATION STUFF                          */
1107 /*****************************************************************************/
1108
1109 CTDL_MODULE_INIT(citserver)
1110 {
1111         if (!threading) {
1112                 CtdlRegisterProtoHook(cmd_noop, "NOOP", "no operation");
1113                 CtdlRegisterProtoHook(cmd_qnop, "QNOP", "no operation with no response");
1114                 CtdlRegisterProtoHook(cmd_quit, "QUIT", "log out and disconnect from server");
1115                 CtdlRegisterProtoHook(cmd_lout, "LOUT", "log out but do not disconnect from server");
1116                 CtdlRegisterProtoHook(cmd_asyn, "ASYN", "enable asynchronous server responses");
1117                 CtdlRegisterProtoHook(cmd_info, "INFO", "fetch server capabilities and configuration");
1118                 CtdlRegisterProtoHook(cmd_mesg, "MESG", "fetch system banners");
1119                 CtdlRegisterProtoHook(cmd_emsg, "EMSG", "submit system banners");
1120                 CtdlRegisterProtoHook(cmd_echo, "ECHO", "echo text back to the client");
1121                 CtdlRegisterProtoHook(cmd_more, "MORE", "fetch the paginator prompt");
1122                 CtdlRegisterProtoHook(cmd_iden, "IDEN", "identify the client software and location");
1123                 CtdlRegisterProtoHook(cmd_ipgm, "IPGM", "perform privilege escalation for internal programs");
1124                 CtdlRegisterProtoHook(cmd_term, "TERM", "terminate another running session");
1125                 CtdlRegisterProtoHook(cmd_down, "DOWN", "perform a server shutdown");
1126                 CtdlRegisterProtoHook(cmd_halt, "HALT", "halt the server without exiting the server process");
1127                 CtdlRegisterProtoHook(cmd_scdn, "SCDN", "schedule or cancel a server shutdown");
1128                 CtdlRegisterProtoHook(cmd_time, "TIME", "fetch the date and time from the server");
1129         }
1130         /* return our id for the Log */
1131         return "citserver";
1132 }