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[citadel.git] / citadel / citserver.c
1 /* 
2  * $Id$
3  *
4  * Main source module for the Citadel server
5  *
6  */
7
8 #include "sysdep.h"
9 #include <stdlib.h>
10 #include <unistd.h>
11 #include <stdio.h>
12 #include <fcntl.h>
13 #include <signal.h>
14 #include <sys/types.h>
15 #include <sys/stat.h>
16
17
18 #if TIME_WITH_SYS_TIME
19 # include <sys/time.h>
20 # include <time.h>
21 #else
22 # if HAVE_SYS_TIME_H
23 #  include <sys/time.h>
24 # else
25 #  include <time.h>
26 # endif
27 #endif
28
29 #if HAVE_BACKTRACE
30 #include <execinfo.h>
31 #endif
32
33 #include <ctype.h>
34 #include <string.h>
35 #include <dirent.h>
36 #include <errno.h>
37 #include <limits.h>
38 #include <netdb.h>
39 #include <sys/types.h>
40 #include <sys/socket.h>
41 #include <netinet/in.h>
42 #include <arpa/inet.h>
43 #include <libcitadel.h>
44 #include "citadel.h"
45 #include "server.h"
46 #include "sysdep_decls.h"
47 #include "threads.h"
48 #include "citserver.h"
49 #include "config.h"
50 #include "database.h"
51 #include "housekeeping.h"
52 #include "user_ops.h"
53 #include "msgbase.h"
54 #include "support.h"
55 #include "locate_host.h"
56 #include "room_ops.h"
57 #include "file_ops.h"
58 #include "policy.h"
59 #include "control.h"
60 #include "euidindex.h"
61
62 #ifndef HAVE_SNPRINTF
63 #include "snprintf.h"
64 #endif
65
66 #include "ctdl_module.h"
67
68
69 struct CitContext *ContextList = NULL;
70 struct CitContext* next_session = NULL;
71 char *unique_session_numbers;
72 int ScheduledShutdown = 0;
73 int do_defrag = 0;
74 time_t server_startup_time;
75 int panic_fd;
76
77 /**
78  * \brief print the actual stack frame.
79  */
80 void cit_backtrace(void)
81 {
82 #ifdef HAVE_BACKTRACE
83         void *stack_frames[50];
84         size_t size, i;
85         char **strings;
86
87
88         size = backtrace(stack_frames, sizeof(stack_frames) / sizeof(void*));
89         strings = backtrace_symbols(stack_frames, size);
90         for (i = 0; i < size; i++) {
91                 if (strings != NULL)
92                         lprintf(1, "%s\n", strings[i]);
93                 else
94                         lprintf(1, "%p\n", stack_frames[i]);
95         }
96         free(strings);
97 #endif
98 }
99
100 /**
101  * \brief print the actual stack frame.
102  */
103 void cit_panic_backtrace(int SigNum)
104 {
105 #ifdef HAVE_BACKTRACE
106         void *stack_frames[10];
107         size_t size, i;
108         char **strings;
109
110         printf("caught signal 11\n");
111         size = backtrace(stack_frames, sizeof(stack_frames) / sizeof(void*));
112         strings = backtrace_symbols(stack_frames, size);
113         for (i = 0; i < size; i++) {
114                 if (strings != NULL)
115                         lprintf(1, "%s\n", strings[i]);
116                 else
117                         lprintf(1, "%p\n", stack_frames[i]);
118         }
119         free(strings);
120 #endif
121         exit(-1);
122 }
123
124 /*
125  * Various things that need to be initialized at startup
126  */
127 void master_startup(void) {
128         struct timeval tv;
129         unsigned int seed;
130         FILE *urandom;
131         struct ctdlroom qrbuf;
132         
133         lprintf(CTDL_DEBUG, "master_startup() started\n");
134         time(&server_startup_time);
135
136         lprintf(CTDL_INFO, "Opening databases\n");
137         open_databases();
138
139         ctdl_thread_internal_init_tsd();
140         
141         CtdlThreadAllocTSD();
142         
143         if (do_defrag) {
144                 defrag_databases();
145         }
146
147         check_ref_counts();
148
149         lprintf(CTDL_INFO, "Creating base rooms (if necessary)\n");
150         create_room(config.c_baseroom,  0, "", 0, 1, 0, VIEW_BBS);
151         create_room(AIDEROOM,           3, "", 0, 1, 0, VIEW_BBS);
152         create_room(SYSCONFIGROOM,      3, "", 0, 1, 0, VIEW_BBS);
153         create_room(config.c_twitroom,  0, "", 0, 1, 0, VIEW_BBS);
154
155         /* The "Local System Configuration" room doesn't need to be visible */
156         if (lgetroom(&qrbuf, SYSCONFIGROOM) == 0) {
157                 qrbuf.QRflags2 |= QR2_SYSTEM;
158                 lputroom(&qrbuf);
159         }
160
161         lprintf(CTDL_INFO, "Seeding the pseudo-random number generator...\n");
162         urandom = fopen("/dev/urandom", "r");
163         if (urandom != NULL) {
164                 fread(&seed, sizeof seed, 1, urandom);
165                 fclose(urandom);
166         }
167         else {
168                 gettimeofday(&tv, NULL);
169                 seed = tv.tv_usec;
170         }
171         srandom(seed);
172
173         lprintf(CTDL_INFO, "Initializing ipgm secret\n");
174         get_config();
175         config.c_ipgm_secret = rand();
176         put_config();
177
178         lprintf(CTDL_DEBUG, "master_startup() finished\n");
179 }
180
181
182 /*
183  * Cleanup routine to be called when the server is shutting down.
184  */
185 void master_cleanup(int exitcode) {
186         struct CleanupFunctionHook *fcn;
187         static int already_cleaning_up = 0;
188
189         if (already_cleaning_up) while(1) sleep(1);
190         already_cleaning_up = 1;
191
192         /* Run any cleanup routines registered by loadable modules */
193         for (fcn = CleanupHookTable; fcn != NULL; fcn = fcn->next) {
194                 (*fcn->h_function_pointer)();
195         }
196
197         /* Close the AdjRefCount queue file */
198         AdjRefCount(-1, 0);
199
200         /* Do system-dependent stuff */
201         sysdep_master_cleanup();
202         
203         /* Close databases */
204         lprintf(CTDL_INFO, "Closing databases\n");
205         close_databases();
206
207 #ifdef DEBUG_MEMORY_LEAKS
208         dump_heap();
209 #endif
210
211         /* If the operator requested a halt but not an exit, halt here. */
212         if (shutdown_and_halt) {
213                 lprintf(CTDL_NOTICE, "citserver: Halting server without exiting.\n");
214                 fflush(stdout); fflush(stderr);
215                 while(1) {
216                         sleep(32767);
217                 }
218         }
219         
220         release_control();
221
222         /* Now go away. */
223         lprintf(CTDL_NOTICE, "citserver: Exiting with status %d\n", exitcode);
224         fflush(stdout); fflush(stderr);
225         
226         if (restart_server != 0)
227                 exit(1);
228         exit(exitcode);
229 }
230
231
232
233 /*
234  * Terminate a session.
235  */
236 void RemoveContext (struct CitContext *con)
237 {
238         if (con==NULL) {
239                 lprintf(CTDL_ERR,
240                         "WARNING: RemoveContext() called with NULL!\n");
241                 return;
242         }
243         lprintf(CTDL_DEBUG, "RemoveContext() session %d\n", con->cs_pid);
244
245         /* Run any cleanup routines registered by loadable modules.
246          * Note: We have to "become_session()" because the cleanup functions
247          *       might make references to "CC" assuming it's the right one.
248          */
249         become_session(con);
250         PerformSessionHooks(EVT_STOP);
251         become_session(NULL);
252
253         /* Now handle all of the administrivia. */
254         lprintf(CTDL_DEBUG, "Calling logout(%d)\n", con->cs_pid);
255         logout(con);
256
257         lprintf(CTDL_NOTICE, "[%3d] Session ended.\n", con->cs_pid);
258
259         /* If the client is still connected, blow 'em away. */
260         lprintf(CTDL_DEBUG, "Closing socket %d\n", con->client_socket);
261         close(con->client_socket);
262
263         lprintf(CTDL_DEBUG, "Done with RemoveContext()\n");
264 }
265
266
267
268
269
270 /*
271  * cmd_info()  -  tell the client about this server
272  */
273 void cmd_info(void) {
274         cprintf("%d Server info:\n", LISTING_FOLLOWS);
275         cprintf("%d\n", CC->cs_pid);
276         cprintf("%s\n", config.c_nodename);
277         cprintf("%s\n", config.c_humannode);
278         cprintf("%s\n", config.c_fqdn);
279         cprintf("%s\n", CITADEL);
280         cprintf("%d\n", REV_LEVEL);
281         cprintf("%s\n", config.c_site_location);
282         cprintf("%s\n", config.c_sysadm);
283         cprintf("%d\n", SERVER_TYPE);
284         cprintf("%s\n", config.c_moreprompt);
285         cprintf("1\n"); /* 1 = yes, this system supports floors */
286         cprintf("1\n"); /* 1 = we support the extended paging options */
287         cprintf("%s\n", CC->cs_nonce);
288         cprintf("1\n"); /* 1 = yes, this system supports the QNOP command */
289
290 #ifdef HAVE_LDAP
291         cprintf("1\n"); /* 1 = yes, this server is LDAP-enabled */
292 #else
293         cprintf("0\n"); /* 1 = no, this server is not LDAP-enabled */
294 #endif
295
296         if (config.c_auth_mode == AUTHMODE_NATIVE) {
297                 cprintf("%d\n", config.c_disable_newu);
298         }
299         else {
300                 cprintf("1\n"); /* "create new user" does not work with non-native auth modes */
301         }
302
303         cprintf("%s\n", config.c_default_cal_zone);
304
305         /* Output load averages */
306         cprintf("%f\n", CtdlThreadLoadAvg);
307         cprintf("%f\n", CtdlThreadWorkerAvg);
308         cprintf("%d\n", CtdlThreadGetCount());
309
310         /* Does this server support Sieve mail filtering? */
311 #ifdef HAVE_LIBSIEVE
312         cprintf("1\n");         /* yes */
313 #else
314         cprintf("0\n");         /* no */
315 #endif
316         
317         cprintf("000\n");
318 }
319
320
321 /*
322  * returns an asterisk if there are any instant messages waiting,
323  * space otherwise.
324  */
325 char CtdlCheckExpress(void) {
326         if (CC->FirstExpressMessage == NULL) {
327                 return(' ');
328         }
329         else {
330                 return('*');
331         }
332 }
333
334 void cmd_time(void)
335 {
336    time_t tv;
337    struct tm tmp;
338    
339    tv = time(NULL);
340    localtime_r(&tv, &tmp);
341    
342    /* timezone and daylight global variables are not portable. */
343 #ifdef HAVE_STRUCT_TM_TM_GMTOFF
344    cprintf("%d %ld|%ld|%d\n", CIT_OK, (long)tv, tmp.tm_gmtoff, tmp.tm_isdst);
345 #else
346    cprintf("%d %ld|%ld|%d\n", CIT_OK, (long)tv, timezone, tmp.tm_isdst);
347 #endif
348 }
349
350
351 /*
352  * Check originating host against the public_clients file.  This determines
353  * whether the client is allowed to change the hostname for this session
354  * (for example, to show the location of the user rather than the location
355  * of the client).
356  */
357 int is_public_client(void)
358 {
359         char buf[1024];
360         char addrbuf[1024];
361         FILE *fp;
362         int i;
363         char *public_clientspos;
364         char *public_clientsend;
365         char *paddr = NULL;
366         struct stat statbuf;
367         static time_t pc_timestamp = 0;
368         static char public_clients[SIZ];
369         static char public_clients_file[SIZ];
370
371 #define LOCALHOSTSTR "127.0.0.1"
372
373         snprintf(public_clients_file, 
374                          sizeof public_clients_file,
375                          "%s/public_clients",
376                          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                 lprintf(CTDL_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                 lprintf(CTDL_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         lprintf(CTDL_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                         lprintf(CTDL_DEBUG, "... yes it is.\n");
445                         return(1);
446                 }
447         }
448
449         /* No hits.  This is not a public client. */
450         lprintf(CTDL_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         struct in_addr addr;
466         int do_lookup = 0;
467
468         if (num_parms(argbuf)<4) {
469                 cprintf("%d usage error\n", ERROR + ILLEGAL_VALUE);
470                 return;
471         }
472
473         dev_code = extract_int(argbuf,0);
474         cli_code = extract_int(argbuf,1);
475         rev_level = extract_int(argbuf,2);
476         extract_token(desc, argbuf, 3, '|', sizeof desc);
477
478         safestrncpy(from_host, config.c_fqdn, sizeof from_host);
479         from_host[sizeof from_host - 1] = 0;
480         if (num_parms(argbuf)>=5) extract_token(from_host, argbuf, 4, '|', sizeof from_host);
481
482         CC->cs_clientdev = dev_code;
483         CC->cs_clienttyp = cli_code;
484         CC->cs_clientver = rev_level;
485         safestrncpy(CC->cs_clientname, desc, sizeof CC->cs_clientname);
486         CC->cs_clientname[31] = 0;
487
488         if (!IsEmptyStr(from_host)) {
489                 if (CC->is_local_socket) do_lookup = 1;
490                 else if (is_public_client()) do_lookup = 1;
491         }
492
493         if (do_lookup) {
494                 lprintf(CTDL_DEBUG, "Looking up hostname '%s'\n", from_host);
495                 if ((addr.s_addr = inet_addr(from_host)) != -1) {
496                         locate_host(CC->cs_host, sizeof CC->cs_host,
497                                 CC->cs_addr, sizeof CC->cs_addr,
498                                 &addr);
499                 }
500                 else {
501                         safestrncpy(CC->cs_host, from_host, sizeof CC->cs_host);
502                         CC->cs_host[sizeof CC->cs_host - 1] = 0;
503                 }
504         }
505
506         lprintf(CTDL_NOTICE, "Client %d/%d/%01d.%02d (%s) from %s\n",
507                 dev_code,
508                 cli_code,
509                 (rev_level / 100),
510                 (rev_level % 100),
511                 desc,
512                 CC->cs_host);
513         cprintf("%d Ok\n",CIT_OK);
514 }
515
516
517 /*
518  * display system messages or help
519  */
520 void cmd_mesg(char *mname)
521 {
522         FILE *mfp;
523         char targ[256];
524         char buf[256];
525         char buf2[256];
526         char *dirs[2];
527         DIR *dp;
528         struct dirent *d;
529
530         extract_token(buf, mname, 0, '|', sizeof buf);
531
532         dirs[0] = strdup(ctdl_message_dir);
533         dirs[1] = strdup(ctdl_hlp_dir);
534
535         snprintf(buf2, sizeof buf2, "%s.%d.%d",
536                 buf, CC->cs_clientdev, CC->cs_clienttyp);
537
538         /* If the client requested "?" then produce a listing */
539         if (!strcmp(buf, "?")) {
540                 cprintf("%d %s\n", LISTING_FOLLOWS, buf);
541                 dp = opendir(dirs[1]);
542                 if (dp != NULL) {
543                         while (d = readdir(dp), d != NULL) {
544                                 if (d->d_name[0] != '.') {
545                                         cprintf(" %s\n", d->d_name);
546                                 }
547                         }
548                         closedir(dp);
549                 }
550                 cprintf("000\n");
551                 free(dirs[0]);
552                 free(dirs[1]);
553                 return;
554         }
555
556         /* Otherwise, look for the requested file by name. */
557         else {
558                 mesg_locate(targ, sizeof targ, buf2, 2, (const char **)dirs);
559                 if (IsEmptyStr(targ)) {
560                         snprintf(buf2, sizeof buf2, "%s.%d",
561                                                         buf, CC->cs_clientdev);
562                         mesg_locate(targ, sizeof targ, buf2, 2,
563                                                         (const char **)dirs);
564                         if (IsEmptyStr(targ)) {
565                                 mesg_locate(targ, sizeof targ, buf, 2,
566                                                         (const char **)dirs);
567                         }       
568                 }
569         }
570
571         free(dirs[0]);
572         free(dirs[1]);
573
574         if (IsEmptyStr(targ)) {
575                 cprintf("%d '%s' not found.  (Searching in %s and %s)\n",
576                         ERROR + FILE_NOT_FOUND,
577                         mname,
578                         ctdl_message_dir,
579                         ctdl_hlp_dir
580                 );
581                 return;
582         }
583
584         mfp = fopen(targ, "r");
585         if (mfp==NULL) {
586                 cprintf("%d Cannot open '%s': %s\n",
587                         ERROR + INTERNAL_ERROR, targ, strerror(errno));
588                 return;
589         }
590         cprintf("%d %s\n", LISTING_FOLLOWS,buf);
591
592         while (fgets(buf, (sizeof buf - 1), mfp) != NULL) {
593                 buf[strlen(buf)-1] = 0;
594                 do_help_subst(buf);
595                 cprintf("%s\n",buf);
596         }
597
598         fclose(mfp);
599         cprintf("000\n");
600 }
601
602
603 /*
604  * enter system messages or help
605  */
606 void cmd_emsg(char *mname)
607 {
608         FILE *mfp;
609         char targ[256];
610         char buf[256];
611         char *dirs[2];
612         int a;
613
614         unbuffer_output();
615
616         if (CtdlAccessCheck(ac_aide)) return;
617
618         extract_token(buf, mname, 0, '|', sizeof buf);
619         for (a=0; !IsEmptyStr(&buf[a]); ++a) {          /* security measure */
620                 if (buf[a] == '/') buf[a] = '.';
621         }
622
623         dirs[0] = strdup(ctdl_message_dir);
624         dirs[1] = strdup(ctdl_hlp_dir);
625
626         mesg_locate(targ, sizeof targ, buf, 2, (const char**)dirs);
627         free(dirs[0]);
628         free(dirs[1]);
629
630         if (IsEmptyStr(targ)) {
631                 snprintf(targ, sizeof targ, 
632                                  "%s/%s",
633                                  ctdl_hlp_dir, buf);
634         }
635
636         mfp = fopen(targ,"w");
637         if (mfp==NULL) {
638                 cprintf("%d Cannot open '%s': %s\n",
639                         ERROR + INTERNAL_ERROR, targ, strerror(errno));
640                 return;
641         }
642         cprintf("%d %s\n", SEND_LISTING, targ);
643
644         while (client_getln(buf, sizeof buf), strcmp(buf, "000")) {
645                 fprintf(mfp, "%s\n", buf);
646         }
647
648         fclose(mfp);
649 }
650
651
652 /* Don't show the names of private rooms unless the viewing
653  * user also knows the rooms.
654  */
655 void GenerateRoomDisplay(char *real_room,
656                         struct CitContext *viewed,
657                         struct CitContext *viewer) {
658
659         int ra;
660
661         strcpy(real_room, viewed->room.QRname);
662         if (viewed->room.QRflags & QR_MAILBOX) {
663                 strcpy(real_room, &real_room[11]);
664         }
665         if (viewed->room.QRflags & QR_PRIVATE) {
666                 CtdlRoomAccess(&viewed->room, &viewer->user, &ra, NULL);
667                 if ( (ra & UA_KNOWN) == 0) {
668                         strcpy(real_room, "<private room>");
669                 }
670         }
671
672         if (viewed->cs_flags & CS_CHAT) {
673                 while (strlen(real_room) < 14) {
674                         strcat(real_room, " ");
675                 }
676                 strcpy(&real_room[14], "<chat>");
677         }
678
679 }
680
681 /*
682  * Convenience function.
683  */
684 int CtdlAccessCheck(int required_level) {
685
686         if (CC->internal_pgm) return(0);
687         if (required_level >= ac_internal) {
688                 cprintf("%d This is not a user-level command.\n",
689                         ERROR + HIGHER_ACCESS_REQUIRED);
690                 return(-1);
691         }
692
693         if ((required_level >= ac_logged_in) && (CC->logged_in == 0)) {
694                 cprintf("%d Not logged in.\n", ERROR + NOT_LOGGED_IN);
695                 return(-1);
696         }
697
698         if (CC->user.axlevel >= 6) return(0);
699         if (required_level >= ac_aide) {
700                 cprintf("%d This command requires Aide access.\n",
701                         ERROR + HIGHER_ACCESS_REQUIRED);
702                 return(-1);
703         }
704
705         if (is_room_aide()) return(0);
706         if (required_level >= ac_room_aide) {
707                 cprintf("%d This command requires Aide or Room Aide access.\n",
708                         ERROR + HIGHER_ACCESS_REQUIRED);
709                 return(-1);
710         }
711
712         /* shhh ... succeed quietly */
713         return(0);
714 }
715
716
717
718 /*
719  * Terminate another running session
720  */
721 void cmd_term(char *cmdbuf)
722 {
723         int session_num;
724         struct CitContext *ccptr;
725         int found_it = 0;
726         int allowed = 0;
727
728         session_num = extract_int(cmdbuf, 0);
729         if (session_num == CC->cs_pid) {
730                 cprintf("%d You can't kill your own session.\n", ERROR + ILLEGAL_VALUE);
731                 return;
732         }
733
734         lprintf(CTDL_DEBUG, "Locating session to kill\n");
735         begin_critical_section(S_SESSION_TABLE);
736         for (ccptr = ContextList; ccptr != NULL; ccptr = ccptr->next) {
737                 if (session_num == ccptr->cs_pid) {
738                         found_it = 1;
739                         if ((ccptr->user.usernum == CC->user.usernum)
740                            || (CC->user.axlevel >= 6)) {
741                                 allowed = 1;
742                                 ccptr->kill_me = 1;
743                         }
744                         else {
745                                 allowed = 0;
746                         }
747                 }
748         }
749         end_critical_section(S_SESSION_TABLE);
750
751         if (found_it) {
752                 if (allowed) {
753                         cprintf("%d Session terminated.\n", CIT_OK);
754                 }
755                 else {
756                         cprintf("%d You are not allowed to do that.\n",
757                                 ERROR + HIGHER_ACCESS_REQUIRED);
758                 }
759         }
760         else {
761                 cprintf("%d No such session.\n", ERROR + ILLEGAL_VALUE);
762         }
763 }
764
765
766
767
768
769 /* 
770  * get the paginator prompt
771  */
772 void cmd_more(void) {
773         cprintf("%d %s\n", CIT_OK, config.c_moreprompt);
774 }
775
776 /*
777  * echo 
778  */
779 void cmd_echo(char *etext)
780 {
781         cprintf("%d %s\n", CIT_OK, etext);
782 }
783
784
785
786 /* 
787  * identify as internal program
788  */
789 void cmd_ipgm(char *argbuf)
790 {
791         int secret;
792
793         secret = extract_int(argbuf, 0);
794
795         /* For security reasons, we do NOT allow this command to run
796          * over the network.  Local sockets only.
797          */
798         if (!CC->is_local_socket) {
799                 sleep(5);
800                 cprintf("%d Authentication failed.\n",
801                         ERROR + PASSWORD_REQUIRED);
802         }
803         else if (secret == config.c_ipgm_secret) {
804                 CC->internal_pgm = 1;
805                 strcpy(CC->curr_user, "<internal program>");
806                 CC->cs_flags = CC->cs_flags|CS_STEALTH;
807                 cprintf("%d Authenticated as an internal program.\n", CIT_OK);
808         }
809         else {
810                 sleep(5);
811                 cprintf("%d Authentication failed.\n",
812                         ERROR + PASSWORD_REQUIRED);
813                 lprintf(CTDL_ERR, "Warning: ipgm authentication failed.\n");
814                 CC->kill_me = 1;
815         }
816
817         /* Now change the ipgm secret for the next round.
818          * (Disabled because it breaks concurrent scripts.  The fact that
819          * we no longer accept IPGM over the network should be sufficient
820          * to prevent brute-force attacks.  If you don't agree, uncomment
821          * this block.)
822         get_config();
823         config.c_ipgm_secret = rand();
824         put_config();
825         */
826 }
827
828
829 /*
830  * Shut down the server
831  */
832 void cmd_down(char *argbuf) {
833         char *Reply ="%d Shutting down server.  Goodbye.\n";
834
835         if (CtdlAccessCheck(ac_aide)) return;
836
837         if (!IsEmptyStr(argbuf))
838         {
839                 int state = CIT_OK;
840                 restart_server = extract_int(argbuf, 0);
841                 
842                 if (restart_server > 0)
843                         Reply = "%d Restarting server.  See you soon.\n";
844                 if ((restart_server > 0) && !running_as_daemon)
845                 {
846                         lprintf(CTDL_ERR, "The user requested restart, but not running as deamon! Geronimooooooo!\n");
847                         Reply = "%d Warning, not running in deamon mode. maybe we will come up again, but don't lean on it.\n";
848                         state = ERROR;
849                 }
850                 cprintf(Reply, state);
851         }
852         else
853         {
854                 cprintf(Reply, CIT_OK + SERVER_SHUTTING_DOWN);
855         }
856         CtdlThreadStopAll();
857 }
858
859 /*
860  * Halt the server without exiting the server process.
861  */
862 void cmd_halt(void) {
863
864         if (CtdlAccessCheck(ac_aide)) return;
865
866         cprintf("%d Halting server.  Goodbye.\n", CIT_OK);
867         CtdlThreadStopAll();
868         shutdown_and_halt = 1;
869 }
870
871 /*
872  * Schedule or cancel a server shutdown
873  */
874 void cmd_scdn(char *argbuf)
875 {
876         int new_state;
877         int state = CIT_OK;
878         char *Reply = "%d %d\n";
879
880         if (CtdlAccessCheck(ac_aide)) return;
881
882         new_state = extract_int(argbuf, 0);
883         if ((new_state == 2) || (new_state == 3))
884         {
885                 restart_server = 1;
886                 if (!running_as_daemon)
887                 {
888                         lprintf(CTDL_ERR, "The user requested restart, but not running as deamon! Geronimooooooo!\n");
889                         Reply = "%d %d Warning, not running in deamon mode. maybe we will come up again, but don't lean on it.\n";
890                         state = ERROR;
891                 }
892
893                 restart_server = extract_int(argbuf, 0);
894                 new_state -= 2;
895         }
896         if ((new_state == 0) || (new_state == 1)) {
897                 ScheduledShutdown = new_state;
898         }
899         cprintf(Reply, state, ScheduledShutdown);
900 }
901
902
903 /*
904  * Set or unset asynchronous protocol mode
905  */
906 void cmd_asyn(char *argbuf)
907 {
908         int new_state;
909
910         new_state = extract_int(argbuf, 0);
911         if ((new_state == 0) || (new_state == 1)) {
912                 CC->is_async = new_state;
913         }
914         cprintf("%d %d\n", CIT_OK, CC->is_async);
915 }
916
917
918 /*
919  * Generate a "nonce" for APOP-style authentication.
920  *
921  * RFC 1725 et al specify a PID to be placed in front of the nonce.
922  * Quoth BTX: That would be stupid.
923  */
924 void generate_nonce(struct CitContext *con) {
925         struct timeval tv;
926
927         memset(con->cs_nonce, NONCE_SIZE, 0);
928         gettimeofday(&tv, NULL);
929         memset(con->cs_nonce, NONCE_SIZE, 0);
930         snprintf(con->cs_nonce, NONCE_SIZE, "<%d%ld@%s>",
931                 rand(), (long)tv.tv_usec, config.c_fqdn);
932 }
933
934
935
936
937 /*
938  * Back-end function for starting a session
939  */
940 void begin_session(struct CitContext *con)
941 {
942         socklen_t len;
943         struct sockaddr_in sin;
944
945         /* 
946          * Initialize some variables specific to our context.
947          */
948         con->logged_in = 0;
949         con->internal_pgm = 0;
950         con->download_fp = NULL;
951         con->upload_fp = NULL;
952         con->FirstExpressMessage = NULL;
953         time(&con->lastcmd);
954         time(&con->lastidle);
955         strcpy(con->lastcmdname, "    ");
956         strcpy(con->cs_clientname, "(unknown)");
957         strcpy(con->curr_user, NLI);
958         *con->net_node = '\0';
959         *con->fake_username = '\0';
960         *con->fake_hostname = '\0';
961         *con->fake_roomname = '\0';
962         generate_nonce(con);
963         safestrncpy(con->cs_host, config.c_fqdn, sizeof con->cs_host);
964         safestrncpy(con->cs_addr, "", sizeof con->cs_addr);
965         con->cs_host[sizeof con->cs_host - 1] = 0;
966         len = sizeof sin;
967         if (!CC->is_local_socket) {
968                 if (!getpeername(con->client_socket, (struct sockaddr *) &sin, &len)) {
969                         locate_host(con->cs_host, sizeof con->cs_host,
970                                 con->cs_addr, sizeof con->cs_addr,
971                                 &sin.sin_addr
972                         );
973                 }
974         }
975         else {
976                 strcpy(con->cs_host, "");
977         }
978         con->cs_flags = 0;
979         con->upload_type = UPL_FILE;
980         con->dl_is_net = 0;
981
982         con->nologin = 0;
983         if ((config.c_maxsessions > 0)&&(num_sessions > config.c_maxsessions)) {
984                 con->nologin = 1;
985         }
986
987         if (!CC->is_local_socket) {
988                 lprintf(CTDL_NOTICE, "Session started from %s [%s].\n", con->cs_host, con->cs_addr);
989         }
990         else {
991                 lprintf(CTDL_NOTICE, "Session started via local socket.\n");
992         }
993
994         /* Run any session startup routines registered by loadable modules */
995         PerformSessionHooks(EVT_START);
996 }
997
998
999 void citproto_begin_session() {
1000         if (CC->nologin==1) {
1001                 cprintf("%d %s: Too many users are already online (maximum is %d)\n",
1002                         ERROR + MAX_SESSIONS_EXCEEDED,
1003                         config.c_nodename, config.c_maxsessions
1004                 );
1005                 CC->kill_me = 1;
1006         }
1007         else {
1008                 cprintf("%d %s Citadel server ready.\n",
1009                         CIT_OK, config.c_nodename);
1010         }
1011 }
1012
1013
1014
1015
1016 /*
1017  * This loop recognizes all server commands.
1018  */
1019 void do_command_loop(void) {
1020         char cmdbuf[SIZ];
1021         const char *old_name = NULL;
1022         
1023         old_name = CtdlThreadName("do_command_loop");
1024         
1025         time(&CC->lastcmd);
1026         memset(cmdbuf, 0, sizeof cmdbuf); /* Clear it, just in case */
1027         if (client_getln(cmdbuf, sizeof cmdbuf) < 1) {
1028                 lprintf(CTDL_ERR, "Client disconnected: ending session.\n");
1029                 CC->kill_me = 1;
1030                 CtdlThreadName(old_name);
1031                 return;
1032         }
1033
1034         /* Log the server command, but don't show passwords... */
1035         if ( (strncasecmp(cmdbuf, "PASS", 4))
1036            && (strncasecmp(cmdbuf, "SETP", 4)) ) {
1037                 lprintf(CTDL_INFO, "%s\n", cmdbuf);
1038         }
1039         else {
1040                 lprintf(CTDL_INFO, "<password command sent>\n");
1041         }
1042
1043         buffer_output();
1044
1045         /*
1046          * Let other clients see the last command we executed, and
1047          * update the idle time, but not NOOP, QNOP, PEXP, GEXP, RWHO, or TIME.
1048          */
1049         if ( (strncasecmp(cmdbuf, "NOOP", 4))
1050            && (strncasecmp(cmdbuf, "QNOP", 4))
1051            && (strncasecmp(cmdbuf, "PEXP", 4))
1052            && (strncasecmp(cmdbuf, "GEXP", 4))
1053            && (strncasecmp(cmdbuf, "RWHO", 4))
1054            && (strncasecmp(cmdbuf, "TIME", 4)) ) {
1055                 strcpy(CC->lastcmdname, "    ");
1056                 safestrncpy(CC->lastcmdname, cmdbuf, sizeof(CC->lastcmdname));
1057                 time(&CC->lastidle);
1058         }
1059         
1060         CtdlThreadName(cmdbuf);
1061                 
1062         if ((strncasecmp(cmdbuf, "ENT0", 4))
1063            && (strncasecmp(cmdbuf, "MESG", 4))
1064            && (strncasecmp(cmdbuf, "MSGS", 4)))
1065         {
1066            CC->cs_flags &= ~CS_POSTING;
1067         }
1068                    
1069         if (!strncasecmp(cmdbuf, "NOOP", 4)) {
1070                 cprintf("%d%cok\n", CIT_OK, CtdlCheckExpress() );
1071         }
1072         
1073         else if (!strncasecmp(cmdbuf, "XYZZY", 5)) {
1074                 cprintf("%d Nothing happens.\n", CIT_OK);
1075         }
1076         
1077         else if (!strncasecmp(cmdbuf, "QNOP", 4)) {
1078                 /* do nothing, this command returns no response */
1079         }
1080
1081         else if (!strncasecmp(cmdbuf,"QUIT",4)) {
1082                 cprintf("%d Goodbye.\n", CIT_OK);
1083                 CC->kill_me = 1;
1084         }
1085
1086         else if (!strncasecmp(cmdbuf,"ASYN",4)) {
1087                 cmd_asyn(&cmdbuf[5]);
1088         }
1089
1090         else if (!strncasecmp(cmdbuf,"LOUT",4)) {
1091                 if (CC->logged_in) logout(CC);
1092                 cprintf("%d logged out.\n", CIT_OK);
1093         }
1094
1095         else if (!strncasecmp(cmdbuf,"USER",4)) {
1096                 cmd_user(&cmdbuf[5]);
1097         }
1098
1099         else if (!strncasecmp(cmdbuf,"PASS",4)) {
1100                 cmd_pass(&cmdbuf[5]);
1101         }
1102
1103         else if (!strncasecmp(cmdbuf,"NEWU",4)) {
1104                 cmd_newu(&cmdbuf[5]);
1105         }
1106
1107         else if (!strncasecmp(cmdbuf,"CREU",4)) {
1108                 cmd_creu(&cmdbuf[5]);
1109         }
1110
1111         else if (!strncasecmp(cmdbuf,"SETP",4)) {
1112                 cmd_setp(&cmdbuf[5]);
1113         }
1114
1115         else if (!strncasecmp(cmdbuf,"LRMS",4)) {
1116                 cmd_lrms(&cmdbuf[5]);
1117         }
1118
1119         else if (!strncasecmp(cmdbuf,"LKRA",4)) {
1120                 cmd_lkra(&cmdbuf[5]);
1121         }
1122
1123         else if (!strncasecmp(cmdbuf,"LKRN",4)) {
1124                 cmd_lkrn(&cmdbuf[5]);
1125         }
1126
1127         else if (!strncasecmp(cmdbuf,"LKRO",4)) {
1128                 cmd_lkro(&cmdbuf[5]);
1129         }
1130
1131         else if (!strncasecmp(cmdbuf,"LZRM",4)) {
1132                 cmd_lzrm(&cmdbuf[5]);
1133         }
1134
1135         else if (!strncasecmp(cmdbuf,"LPRM",4)) {
1136                 cmd_lprm(&cmdbuf[5]);
1137         }
1138
1139         else if (!strncasecmp(cmdbuf,"GETU",4)) {
1140                 cmd_getu();
1141         }
1142
1143         else if (!strncasecmp(cmdbuf,"SETU",4)) {
1144                 cmd_setu(&cmdbuf[5]);
1145         }
1146
1147         else if (!strncasecmp(cmdbuf,"GOTO",4)) {
1148                 cmd_goto(&cmdbuf[5]);
1149         }
1150
1151         else if (!strncasecmp(cmdbuf,"MSGS",4)) {
1152                 cmd_msgs(&cmdbuf[5]);
1153         }
1154
1155         else if (!strncasecmp(cmdbuf,"WHOK",4)) {
1156                 cmd_whok();
1157         }
1158
1159         else if (!strncasecmp(cmdbuf,"RDIR",4)) {
1160                 cmd_rdir();
1161         }
1162
1163         else if (!strncasecmp(cmdbuf,"EUID",4)) {
1164                 cmd_euid(&cmdbuf[5]);
1165         }
1166
1167         else if (!strncasecmp(cmdbuf,"MSG0",4)) {
1168                 cmd_msg0(&cmdbuf[5]);
1169         }
1170
1171         else if (!strncasecmp(cmdbuf,"MSG2",4)) {
1172                 cmd_msg2(&cmdbuf[5]);
1173         }
1174
1175         else if (!strncasecmp(cmdbuf,"MSG3",4)) {
1176                 cmd_msg3(&cmdbuf[5]);
1177         }
1178
1179         else if (!strncasecmp(cmdbuf,"MSG4",4)) {
1180                 cmd_msg4(&cmdbuf[5]);
1181         }
1182
1183         else if (!strncasecmp(cmdbuf,"MSGP",4)) {
1184                 cmd_msgp(&cmdbuf[5]);
1185         }
1186
1187         else if (!strncasecmp(cmdbuf,"OPNA",4)) {
1188                 cmd_opna(&cmdbuf[5]);
1189         }
1190
1191         else if (!strncasecmp(cmdbuf,"DLAT",4)) {
1192                 cmd_dlat(&cmdbuf[5]);
1193         }
1194
1195         else if (!strncasecmp(cmdbuf,"INFO",4)) {
1196                 cmd_info();
1197         }
1198
1199         else if (!strncasecmp(cmdbuf,"SLRP",4)) {
1200                 cmd_slrp(&cmdbuf[5]);
1201         }
1202
1203         else if (!strncasecmp(cmdbuf,"INVT",4)) {
1204                 cmd_invt_kick(&cmdbuf[5],1);
1205         }
1206
1207         else if (!strncasecmp(cmdbuf,"KICK",4)) {
1208                 cmd_invt_kick(&cmdbuf[5],0);
1209         }
1210
1211         else if (!strncasecmp(cmdbuf,"GETR",4)) {
1212                 cmd_getr();
1213         }
1214
1215         else if (!strncasecmp(cmdbuf,"SETR",4)) {
1216                 cmd_setr(&cmdbuf[5]);
1217         }
1218
1219         else if (!strncasecmp(cmdbuf,"GETA",4)) {
1220                 cmd_geta();
1221         }
1222
1223         else if (!strncasecmp(cmdbuf,"SETA",4)) {
1224                 cmd_seta(&cmdbuf[5]);
1225         }
1226
1227         else if (!strncasecmp(cmdbuf,"ENT0",4)) {
1228                 cmd_ent0(&cmdbuf[5]);
1229         }
1230
1231         else if (!strncasecmp(cmdbuf,"RINF",4)) {
1232                 cmd_rinf();
1233         }
1234
1235         else if (!strncasecmp(cmdbuf,"DELE",4)) {
1236                 cmd_dele(&cmdbuf[5]);
1237         }
1238
1239         else if (!strncasecmp(cmdbuf,"KILL",4)) {
1240                 cmd_kill(&cmdbuf[5]);
1241         }
1242
1243         else if (!strncasecmp(cmdbuf,"CRE8",4)) {
1244                 cmd_cre8(&cmdbuf[5]);
1245         }
1246
1247         else if (!strncasecmp(cmdbuf,"MOVE",4)) {
1248                 cmd_move(&cmdbuf[5]);
1249         }
1250
1251         else if (!strncasecmp(cmdbuf,"FORG",4)) {
1252                 cmd_forg();
1253         }
1254
1255         else if (!strncasecmp(cmdbuf,"MESG",4)) {
1256                 cmd_mesg(&cmdbuf[5]);
1257         }
1258
1259         else if (!strncasecmp(cmdbuf,"EMSG",4)) {
1260                 cmd_emsg(&cmdbuf[5]);
1261         }
1262
1263         else if (!strncasecmp(cmdbuf,"GNUR",4)) {
1264                 cmd_gnur();
1265         }
1266
1267         else if (!strncasecmp(cmdbuf,"VALI",4)) {
1268                 cmd_vali(&cmdbuf[5]);
1269         }
1270
1271         else if (!strncasecmp(cmdbuf,"EINF",4)) {
1272                 cmd_einf(&cmdbuf[5]);
1273         }
1274
1275         else if (!strncasecmp(cmdbuf,"LIST",4)) {
1276                 cmd_list(&cmdbuf[5]);
1277         }
1278
1279         else if (!strncasecmp(cmdbuf,"CHEK",4)) {
1280                 cmd_chek();
1281         }
1282
1283         else if (!strncasecmp(cmdbuf,"DELF",4)) {
1284                 cmd_delf(&cmdbuf[5]);
1285         }
1286
1287         else if (!strncasecmp(cmdbuf,"MOVF",4)) {
1288                 cmd_movf(&cmdbuf[5]);
1289         }
1290
1291         else if (!strncasecmp(cmdbuf,"NETF",4)) {
1292                 cmd_netf(&cmdbuf[5]);
1293         }
1294
1295         else if (!strncasecmp(cmdbuf,"OPEN",4)) {
1296                 cmd_open(&cmdbuf[5]);
1297         }
1298
1299         else if (!strncasecmp(cmdbuf,"CLOS",4)) {
1300                 cmd_clos();
1301         }
1302
1303         else if (!strncasecmp(cmdbuf,"UOPN",4)) {
1304                 cmd_uopn(&cmdbuf[5]);
1305         }
1306
1307         else if (!strncasecmp(cmdbuf,"UCLS",4)) {
1308                 cmd_ucls(&cmdbuf[5]);
1309         }
1310
1311         else if (!strncasecmp(cmdbuf,"READ",4)) {
1312                 cmd_read(&cmdbuf[5]);
1313         }
1314
1315         else if (!strncasecmp(cmdbuf,"WRIT",4)) {
1316                 cmd_writ(&cmdbuf[5]);
1317         }
1318
1319         else if (!strncasecmp(cmdbuf,"QUSR",4)) {
1320                 cmd_qusr(&cmdbuf[5]);
1321         }
1322
1323         else if (!strncasecmp(cmdbuf,"ECHO",4)) {
1324                 cmd_echo(&cmdbuf[5]);
1325         }
1326
1327         else if (!strncasecmp(cmdbuf,"OIMG",4)) {
1328                 cmd_oimg(&cmdbuf[5]);
1329         }
1330
1331         else if (!strncasecmp(cmdbuf,"MORE",4)) {
1332                 cmd_more();
1333         }
1334
1335         else if (!strncasecmp(cmdbuf,"NDOP",4)) {
1336                 cmd_ndop(&cmdbuf[5]);
1337         }
1338
1339         else if (!strncasecmp(cmdbuf,"NUOP",4)) {
1340                 cmd_nuop(&cmdbuf[5]);
1341         }
1342
1343         else if (!strncasecmp(cmdbuf,"LFLR",4)) {
1344                 cmd_lflr();
1345         }
1346
1347         else if (!strncasecmp(cmdbuf,"CFLR",4)) {
1348                 cmd_cflr(&cmdbuf[5]);
1349         }
1350
1351         else if (!strncasecmp(cmdbuf,"KFLR",4)) {
1352                 cmd_kflr(&cmdbuf[5]);
1353         }
1354
1355         else if (!strncasecmp(cmdbuf,"EFLR",4)) {
1356                 cmd_eflr(&cmdbuf[5]);
1357         }
1358
1359         else if (!strncasecmp(cmdbuf,"IDEN",4)) {
1360                 cmd_iden(&cmdbuf[5]);
1361         }
1362
1363         else if (!strncasecmp(cmdbuf,"IPGM",4)) {
1364                 cmd_ipgm(&cmdbuf[5]);
1365         }
1366
1367         else if (!strncasecmp(cmdbuf,"TERM",4)) {
1368                 cmd_term(&cmdbuf[5]);
1369         }
1370
1371         else if (!strncasecmp(cmdbuf,"DOWN",4)) {
1372                 cmd_down(&cmdbuf[5]);
1373         }
1374
1375         else if (!strncasecmp(cmdbuf,"HALT",4)) {
1376                 cmd_halt();
1377         }
1378
1379         else if (!strncasecmp(cmdbuf,"SCDN",4)) {
1380                 cmd_scdn(&cmdbuf[5]);
1381         }
1382
1383         else if (!strncasecmp(cmdbuf, "UIMG", 4)) {
1384                 cmd_uimg(&cmdbuf[5]);
1385         }
1386
1387         else if (!strncasecmp(cmdbuf, "TIME", 4)) {
1388                 cmd_time();
1389         }
1390
1391         else if (!strncasecmp(cmdbuf, "AGUP", 4)) {
1392                 cmd_agup(&cmdbuf[5]);
1393         }
1394
1395         else if (!strncasecmp(cmdbuf, "ASUP", 4)) {
1396                 cmd_asup(&cmdbuf[5]);
1397         }
1398
1399         else if (!strncasecmp(cmdbuf, "GPEX", 4)) {
1400                 cmd_gpex(&cmdbuf[5]);
1401         }
1402
1403         else if (!strncasecmp(cmdbuf, "SPEX", 4)) {
1404                 cmd_spex(&cmdbuf[5]);
1405         }
1406
1407         else if (!strncasecmp(cmdbuf, "CONF", 4)) {
1408                 cmd_conf(&cmdbuf[5]);
1409         }
1410
1411         else if (!strncasecmp(cmdbuf, "SEEN", 4)) {
1412                 cmd_seen(&cmdbuf[5]);
1413         }
1414
1415         else if (!strncasecmp(cmdbuf, "GTSN", 4)) {
1416                 cmd_gtsn(&cmdbuf[5]);
1417         }
1418
1419         else if (!strncasecmp(cmdbuf, "VIEW", 4)) {
1420                 cmd_view(&cmdbuf[5]);
1421         }
1422
1423         else if (!strncasecmp(cmdbuf, "ISME", 4)) {
1424                 cmd_isme(&cmdbuf[5]);
1425         }
1426
1427         else if (!DLoader_Exec_Cmd(cmdbuf)) {
1428                 cprintf("%d Unrecognized or unsupported command.\n", ERROR + CMD_NOT_SUPPORTED);
1429         }
1430
1431         unbuffer_output();
1432
1433         /* Run any after-each-command routines registered by modules */
1434         PerformSessionHooks(EVT_CMD);
1435         CtdlThreadName(old_name);
1436 }
1437
1438
1439 /*
1440  * This loop performs all asynchronous functions.
1441  */
1442 void do_async_loop(void) {
1443         PerformSessionHooks(EVT_ASYNC);
1444 }