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