7b8cc1af8b34c952698e273f2b6f47559b9c5c29
[citadel.git] / citadel / citserver.c
1 /* $Id$ */
2 #include "sysdep.h"
3 #include <stdlib.h>
4 #include <unistd.h>
5 #include <stdio.h>
6 #include <fcntl.h>
7 #include <signal.h>
8 #include <time.h>
9 #include <ctype.h>
10 #include <string.h>
11 #include <errno.h>
12 #include <limits.h>
13 #include <syslog.h>
14 #include <dlfcn.h>
15 #include <netdb.h>
16 #include <sys/types.h>
17 #include <sys/socket.h>
18 #include <netinet/in.h>
19 #include <arpa/inet.h>
20 #include "citadel.h"
21 #include "server.h"
22 #include "sysdep_decls.h"
23 #include "citserver.h"
24 #include "config.h"
25 #include "database.h"
26 #include "housekeeping.h"
27 #include "user_ops.h"
28 #include "logging.h"
29 #include "msgbase.h"
30 #include "support.h"
31 #include "locate_host.h"
32 #include "room_ops.h"
33 #include "file_ops.h"
34 #include "dynloader.h"
35 #include "policy.h"
36 #include "control.h"
37 #include "tools.h"
38
39 struct CitContext *ContextList = NULL;
40 char *unique_session_numbers;
41 int ScheduledShutdown = 0;
42 int do_defrag = 0;
43
44 /*
45  * Various things that need to be initialized at startup
46  */
47 void master_startup(void) {
48         lprintf(7, "Opening databases\n");
49         open_databases();
50
51         if (do_defrag)
52                 defrag_databases();
53
54         lprintf(7, "Checking floor reference counts\n");
55         check_ref_counts();
56
57         lprintf(7, "Creating base rooms (if necessary)\n");
58         create_room(BASEROOM, 0, "", 0);
59         create_room(AIDEROOM, 4, "", 0);
60         create_room(config.c_twitroom, 0, "", 0);
61         }
62
63 /*
64  * Cleanup routine to be called when the server is shutting down.
65  */
66 void master_cleanup(void) {
67         struct CleanupFunctionHook *fcn;
68
69         /* Cancel all running sessions */
70         lprintf(7, "Cancelling running sessions...\n");
71
72 /* FIX do something here
73         while (ContextList != NULL) {
74                 }
75  */
76
77         /* Run any cleanup routines registered by loadable modules */
78         for (fcn = CleanupHookTable; fcn != NULL; fcn = fcn->next) {
79                 (*fcn->h_function_pointer)();
80                 }
81
82         /* Close databases */
83         lprintf(7, "Closing databases\n");
84         close_databases();
85
86         /* Do system-dependent stuff */
87         sysdep_master_cleanup();
88
89         /* Now go away. */
90         lprintf(3, "citserver: exiting.\n");
91         fflush(stdout); fflush(stderr);
92         exit(0);
93         }
94
95
96 /*
97  * Free any per-session data allocated by modules or whatever
98  */
99 void deallocate_user_data(struct CitContext *con)
100 {
101         struct CtdlSessData *ptr;
102
103         begin_critical_section(S_SESSION_TABLE);
104         while (con->FirstSessData != NULL) {
105                 lprintf(9, "Deallocating user data symbol %ld\n",
106                         con->FirstSessData->sym_id);
107                 if (con->FirstSessData->sym_data != NULL)
108                         phree(con->FirstSessData->sym_data);
109                 ptr = con->FirstSessData->next;
110                 phree(con->FirstSessData);
111                 con->FirstSessData = ptr;
112         }
113         end_critical_section(S_SESSION_TABLE);
114 }
115
116
117
118
119 /*
120  * Terminate a session and remove its context data structure.
121  */
122 void RemoveContext (struct CitContext *con)
123 {
124         struct CitContext *ptr = NULL;
125         struct CitContext *ToFree = NULL;
126
127         lprintf(9, "RemoveContext() called\n");
128         if (con==NULL) {
129                 lprintf(5, "WARNING: RemoveContext() called with NULL!\n");
130                 return;
131                 }
132
133         /* Remove the context from the global context list.  This needs
134          * to get done FIRST to avoid concurrency problems.  It is *vitally*
135          * important to keep num_sessions accurate!!
136          */
137         lprintf(7, "Removing context for session %d\n", con->cs_pid);
138         begin_critical_section(S_SESSION_TABLE);
139         if (ContextList == con) {
140                 ToFree = ContextList;
141                 ContextList = ContextList->next;
142                 --num_sessions;
143                 }
144         else {
145                 for (ptr = ContextList; ptr != NULL; ptr = ptr->next) {
146                         if (ptr->next == con) {
147                                 ToFree = ptr->next;
148                                 ptr->next = ptr->next->next;
149                                 --num_sessions;
150                                 }
151                         }
152                 }
153         end_critical_section(S_SESSION_TABLE);
154
155         if (ToFree == NULL) {
156                 lprintf(9, "RemoveContext() found nothing to remove\n");
157                 return;
158         }
159
160         /* Now handle all of the administrivia. */
161         lprintf(7, "Calling logout(%d)\n", con->cs_pid);
162         logout(con);
163
164         rec_log(CL_TERMINATE, con->curr_user);
165         unlink(con->temp);
166         lprintf(3, "citserver[%3d]: ended.\n", con->cs_pid);
167         
168         /* Run any cleanup routines registered by loadable modules */
169         PerformSessionHooks(EVT_STOP);
170
171         syslog(LOG_NOTICE,"session %d ended", con->cs_pid);
172         
173         /* Deallocate any user-data attached to this session */
174         deallocate_user_data(con);
175
176         /* If the client is still connected, blow 'em away. */
177         lprintf(7, "Closing socket %d\n", con->client_socket);
178         close(con->client_socket);
179
180         /* Tell the housekeeping thread to check to see if this is the time
181          * to initiate a scheduled shutdown event.
182          */
183         enter_housekeeping_cmd("SCHED_SHUTDOWN");
184
185         /* Free up the memory used by this context */
186         phree(con);
187
188         lprintf(7, "Done with RemoveContext()\n");
189 }
190
191
192
193 /*
194  * Get a dynamic symbol number for per-session user data.
195  * This API call should be made only ONCE per symbol per citserver run.
196  */
197 int CtdlGetDynamicSymbol() 
198 {
199         static unsigned int next_symbol = SYM_MAX;
200         return ++next_symbol;
201 }
202
203
204
205 /*
206  * Return a pointer to some generic per-session user data.
207  * (This function returns NULL if the requested symbol is not allocated.)
208  *
209  * NOTE: we use critical sections for allocating and de-allocating these,
210  *       but not for locating one.
211  */
212 void *CtdlGetUserData(unsigned long requested_sym) 
213 {
214         struct CtdlSessData *ptr;
215
216         for (ptr = CC->FirstSessData; ptr != NULL; ptr = ptr->next)
217                 if (ptr->sym_id == requested_sym)
218                         return(ptr->sym_data);
219
220         lprintf(2, "ERROR! CtdlGetUserData(%ld) symbol not allocated\n",
221                 requested_sym);
222         return NULL;
223 }
224
225
226 /*
227  * Allocate some generic per-session user data.
228  */
229 void CtdlAllocUserData(unsigned long requested_sym, size_t num_bytes)
230 {
231         struct CtdlSessData *ptr;
232
233         lprintf(9, "CtdlAllocUserData(%ld) called\n", requested_sym);
234
235         /* Fail silently if the symbol is already registered. */
236         for (ptr = CC->FirstSessData; ptr != NULL; ptr = ptr->next)  {
237                 if (ptr->sym_id == requested_sym) {
238                         return;
239                 }
240         }
241
242         /* Grab us some memory!  Dem's good eatin' !!  */
243         ptr = mallok(sizeof(struct CtdlSessData));
244         ptr->sym_id = requested_sym;
245         ptr->sym_data = mallok(num_bytes);
246
247         begin_critical_section(S_SESSION_TABLE);
248         ptr->next = CC->FirstSessData;
249         CC->FirstSessData = ptr;
250         end_critical_section(S_SESSION_TABLE);
251
252         lprintf(9, "CtdlAllocUserData(%ld) finished\n", requested_sym);
253 }
254
255
256
257
258
259
260 /*
261  * cmd_info()  -  tell the client about this server
262  */
263 void cmd_info(void) {
264         cprintf("%d Server info:\n",LISTING_FOLLOWS);
265         cprintf("%d\n",CC->cs_pid);
266         cprintf("%s\n",config.c_nodename);
267         cprintf("%s\n",config.c_humannode);
268         cprintf("%s\n",config.c_fqdn);
269         cprintf("%s\n",CITADEL);
270         cprintf("%d\n",REV_LEVEL);
271         cprintf("%s\n",config.c_bbs_city);
272         cprintf("%s\n",config.c_sysadm);
273         cprintf("%d\n",SERVER_TYPE);
274         cprintf("%s\n",config.c_moreprompt);
275         cprintf("1\n"); /* 1 = yes, this system supports floors */
276         cprintf("1\n"); /* 1 = we support the extended paging options */
277         cprintf("000\n");
278         }
279
280 void cmd_rchg(char *argbuf)
281 {
282         char newroomname[256];
283
284         extract(newroomname, argbuf, 0);
285         newroomname[ROOMNAMELEN-1] = 0;
286         if (strlen(newroomname) > 0) {
287                 safestrncpy(CC->fake_roomname, newroomname,
288                         sizeof(CC->fake_roomname) );
289                 }
290         else {
291                 strcpy(CC->fake_roomname, "");
292                 }
293         cprintf("%d OK\n", OK);
294 }
295
296 void cmd_hchg(char *argbuf)
297 {
298         char newhostname[256];
299
300         extract(newhostname, argbuf, 0);
301         if (strlen(newhostname) > 0) {
302                 safestrncpy(CC->fake_hostname, newhostname,
303                         sizeof(CC->fake_hostname) );
304                 }
305         else {
306                 strcpy(CC->fake_hostname, "");
307                 }
308         cprintf("%d OK\n", OK);
309 }
310
311 void cmd_uchg(char *argbuf)
312 {
313
314         char newusername[256];
315
316         extract(newusername, argbuf, 0);
317
318         if (CC->usersupp.axlevel < 6) {
319                 cprintf("%d You must be an Aide to masquerade your name.\n",
320                         ERROR+HIGHER_ACCESS_REQUIRED);
321                 return;
322         }
323
324         if (strlen(newusername) > 0) {
325                 CC->cs_flags &= ~CS_STEALTH;
326                 memset(CC->fake_username, 0, 32);
327                 if (strncasecmp(newusername, CC->curr_user,
328                                 strlen(CC->curr_user)))
329                         safestrncpy(CC->fake_username, newusername,
330                                 sizeof(CC->fake_username));
331         }
332         else {
333                 CC->fake_username[0] = '\0';
334                 CC->cs_flags |= CS_STEALTH;
335         }
336         cprintf("%d\n",OK);
337 }
338
339
340
341 /*
342  * returns an asterisk if there are any express messages waiting,
343  * space otherwise.
344  */
345 char check_express(void) {
346         if (CC->FirstExpressMessage == NULL) {
347                 return(' ');
348                 }
349         else {
350                 return('*');
351                 }
352         }
353
354 void cmd_time(void)
355 {
356    time_t tv;
357    
358    tv = time(NULL);
359    
360    cprintf("%d %ld\n", OK, tv);
361 }
362
363 /*
364  * Check whether two hostnames match.
365  * "Realname" should be an actual name of a client that is trying to connect;
366  * "testname" should be the value we are comparing it with. The idea is that we
367  * want to compare with both the abbreviated and fully-qualified versions of
368  * "testname;" some people define "localhost" as "localhost.foo.com," etc.
369  */
370 static int hostnames_match(const char *realname, const char *testname) {
371         struct hostent *he;
372         int retval = 0;
373
374         if (!strcasecmp(realname, testname))
375                 return 1;
376
377 #ifdef HAVE_NONREENTRANT_NETDB
378         begin_critical_section(S_NETDB);
379 #endif
380
381         if ((he = gethostbyname(testname)) != NULL)
382                 if (!strcasecmp(realname, he->h_name))
383                         retval = 1;
384
385 #ifdef HAVE_NONREENTRANT_NETDB
386         end_critical_section(S_NETDB);
387 #endif
388
389         return retval;
390         }
391
392 /*
393  * check a hostname against the public_clients file
394  */
395 int is_public_client(char *where)
396 {
397         char buf[256];
398         FILE *fp;
399
400         if (hostnames_match(where,"localhost")) return(1);
401         if (hostnames_match(where,config.c_fqdn)) return(1);
402
403         fp = fopen("public_clients","r");
404         if (fp == NULL) return(0);
405
406         while (fgets(buf,256,fp)!=NULL) {
407                 while (isspace((buf[strlen(buf)-1]))) 
408                         buf[strlen(buf)-1] = 0;
409                 if (hostnames_match(where,buf)) {
410                         fclose(fp);
411                         return(1);
412                         }
413                 }
414
415         fclose(fp);
416         return(0);
417         }
418
419
420 /*
421  * the client is identifying itself to the server
422  */
423 void cmd_iden(char *argbuf)
424 {
425         int dev_code;
426         int cli_code;
427         int rev_level;
428         char desc[256];
429         char from_host[256];
430         struct in_addr addr;
431
432         if (num_parms(argbuf)<4) {
433                 cprintf("%d usage error\n",ERROR);
434                 return;
435                 }
436
437         dev_code = extract_int(argbuf,0);
438         cli_code = extract_int(argbuf,1);
439         rev_level = extract_int(argbuf,2);
440         extract(desc,argbuf,3);
441
442         safestrncpy(from_host, config.c_fqdn, sizeof from_host);
443         from_host[sizeof from_host - 1] = 0;
444         if (num_parms(argbuf)>=5) extract(from_host,argbuf,4);
445
446         CC->cs_clientdev = dev_code;
447         CC->cs_clienttyp = cli_code;
448         CC->cs_clientver = rev_level;
449         safestrncpy(CC->cs_clientname, desc, sizeof CC->cs_clientname);
450         CC->cs_clientname[31] = 0;
451
452         lprintf(9, "Looking up hostname '%s'\n", from_host);
453         if ((strlen(from_host)>0) && 
454            (is_public_client(CC->cs_host))) {
455                 if ((addr.s_addr = inet_addr(from_host)) != INADDR_NONE)
456                         locate_host(CC->cs_host, &addr);
457                 else {
458                         safestrncpy(CC->cs_host, from_host, sizeof CC->cs_host);
459                         CC->cs_host[24] = 0;
460                         }
461                 }
462
463         syslog(LOG_NOTICE,"client %d/%d/%01d.%02d (%s)\n",
464                 dev_code,
465                 cli_code,
466                 (rev_level / 100),
467                 (rev_level % 100),
468                 desc);
469                 cprintf("%d Ok\n",OK);
470         }
471
472
473 /*
474  * enter or exit "stealth mode"
475  */
476 void cmd_stel(char *cmdbuf)
477 {
478         int requested_mode;
479
480         requested_mode = extract_int(cmdbuf,0);
481         if (requested_mode !=0) requested_mode = 1;
482
483         if (!CC->logged_in) {
484                 cprintf("%d Not logged in.\n",ERROR+NOT_LOGGED_IN);
485                 return;
486                 }
487
488         if (CC->usersupp.axlevel < 6) {
489                 cprintf("%d You must be an Aide to use stealth mode.\n",
490                         ERROR+HIGHER_ACCESS_REQUIRED);
491                 return;
492                 }
493
494         if (CC->cs_flags & CS_STEALTH) {
495                 if (requested_mode == 0)
496                         CC->cs_flags = CC->cs_flags-CS_STEALTH;
497                 }
498         else {
499                 if (requested_mode == 1)
500                         CC->cs_flags = CC->cs_flags|CS_STEALTH;
501                 }
502
503         cprintf("%d Ok\n",OK);
504         }
505
506
507
508
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 *dirs[2];
518
519         extract(buf,mname,0);
520
521
522         dirs[0]=mallok(64);
523         dirs[1]=mallok(64);
524         strcpy(dirs[0],"messages");
525         strcpy(dirs[1],"help");
526         mesg_locate(targ,buf,2,dirs);
527         phree(dirs[0]);
528         phree(dirs[1]);
529
530
531         if (strlen(targ)==0) {
532                 cprintf("%d '%s' not found.\n",ERROR,mname);
533                 return;
534                 }
535
536         mfp = fopen(targ,"r");
537         if (mfp==NULL) {
538                 cprintf("%d Cannot open '%s': %s\n",
539                         ERROR,targ,strerror(errno));
540                 return;
541                 }
542         cprintf("%d %s\n",LISTING_FOLLOWS,buf);
543
544         while (fgets(buf,255,mfp)!=NULL) {
545                 buf[strlen(buf)-1] = 0;
546                 do_help_subst(buf);
547                 cprintf("%s\n",buf);
548                 }
549
550         fclose(mfp);
551         cprintf("000\n");
552         }
553
554
555 /*
556  * enter system messages or help
557  */
558 void cmd_emsg(char *mname)
559 {
560         FILE *mfp;
561         char targ[256];
562         char buf[256];
563         char *dirs[2];
564         int a;
565
566         if (CC->usersupp.axlevel < 6) {
567                 cprintf("%d You must be an Aide to edit system messages.\n",
568                         ERROR+HIGHER_ACCESS_REQUIRED);
569                 return;
570                 }
571
572         extract(buf,mname,0);
573         for (a=0; a<strlen(buf); ++a) {         /* security measure */
574                 if (buf[a] == '/') buf[a] = '.';
575                 }
576
577         dirs[0]=mallok(64);
578         dirs[1]=mallok(64);
579         strcpy(dirs[0],"messages");
580         strcpy(dirs[1],"help");
581         mesg_locate(targ,buf,2,dirs);
582         phree(dirs[0]);
583         phree(dirs[1]);
584
585         if (strlen(targ)==0) {
586                 snprintf(targ, sizeof targ, "./help/%s", buf);
587                 }
588
589         mfp = fopen(targ,"w");
590         if (mfp==NULL) {
591                 cprintf("%d Cannot open '%s': %s\n",
592                         ERROR,targ,strerror(errno));
593                 return;
594                 }
595         cprintf("%d %s\n", SEND_LISTING, targ);
596
597         while (client_gets(buf), strcmp(buf, "000")) {
598                 fprintf(mfp, "%s\n", buf);
599                 }
600
601         fclose(mfp);
602         }
603
604
605 /* Don't show the names of private rooms unless the viewing
606  * user also knows the rooms.
607  */
608 void GenerateRoomDisplay(char *real_room,
609                         struct CitContext *viewed,
610                         struct CitContext *viewer) {
611
612         strcpy(real_room, viewed->quickroom.QRname);
613         if (viewed->quickroom.QRflags & QR_MAILBOX) {
614                 strcpy(real_room, &real_room[11]);
615         }
616         if (viewed->quickroom.QRflags & QR_PRIVATE) {
617                 if ( (CtdlRoomAccess(&viewed->quickroom, &viewer->usersupp)
618                    & UA_KNOWN) == 0) {
619                         strcpy(real_room, "<private room>");
620                 }
621         }
622
623         if (viewed->cs_flags & CS_CHAT) {
624                 while (strlen(real_room) < 14)
625                         strcat(real_room, " ");
626
627                 strcpy(&real_room[14], "<chat>");
628         }
629
630 }
631
632
633 /*
634  * who's online
635  */
636 void cmd_rwho(void) {
637         struct CitContext *cptr;
638         int spoofed = 0;
639         int aide;
640         char un[40];
641         char real_room[ROOMNAMELEN], room[ROOMNAMELEN];
642         char host[40], flags[5];
643         
644         aide = CC->usersupp.axlevel >= 6;
645         cprintf("%d%c \n", LISTING_FOLLOWS, check_express() );
646         
647         for (cptr = ContextList; cptr != NULL; cptr = cptr->next) 
648         {
649                 flags[0] = '\0';
650                 spoofed = 0;
651                 
652                 if (cptr->cs_flags & CS_POSTING)
653                    strcat(flags, "*");
654                 else
655                    strcat(flags, ".");
656                    
657                 if (cptr->fake_username[0])
658                 {
659                    strcpy(un, cptr->fake_username);
660                    spoofed = 1;
661                 }
662                 else
663                    strcpy(un, cptr->curr_user);
664                    
665                 if (cptr->fake_hostname[0])
666                 {
667                    strcpy(host, cptr->fake_hostname);
668                    spoofed = 1;
669                 }
670                 else
671                    strcpy(host, cptr->cs_host);
672
673                 GenerateRoomDisplay(real_room, cptr, CC);
674
675                 if (cptr->fake_roomname[0]) {
676                         strcpy(room, cptr->fake_roomname);
677                         spoofed = 1;
678                 }
679                 else {
680                         strcpy(room, real_room);
681                 }
682                 
683                 if ((aide) && (spoofed))
684                    strcat(flags, "+");
685                 
686                 if ((cptr->cs_flags & CS_STEALTH) && (aide))
687                    strcat(flags, "-");
688                 
689                 if (((cptr->cs_flags&CS_STEALTH)==0) || (aide))
690                 {
691                         cprintf("%d|%s|%s|%s|%s|%ld|%s|%s\n",
692                                 cptr->cs_pid, un, room,
693                                 host, cptr->cs_clientname,
694                                 (long)(cptr->lastidle),
695                                 cptr->lastcmdname, flags);
696                 }
697                 if ((spoofed) && (aide))
698                 {
699                         cprintf("%d|%s|%s|%s|%s|%ld|%s|%s\n",
700                                 cptr->cs_pid, cptr->curr_user,
701                                 real_room,
702                                 cptr->cs_host, cptr->cs_clientname,
703                                 (long)(cptr->lastidle),
704                                 cptr->lastcmdname, flags);
705                 
706                 }
707         }
708
709         /* Now it's magic time.  Before we finish, call any EVT_RWHO hooks
710          * so that external paging modules such as serv_icq can add more
711          * content to the Wholist.
712          */
713         PerformSessionHooks(EVT_RWHO);
714         cprintf("000\n");
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
727         if (!CC->logged_in) {
728                 cprintf("%d Not logged in.\n",ERROR+NOT_LOGGED_IN);
729                 return;
730                 }
731
732         if (CC->usersupp.axlevel < 6) {
733                 cprintf("%d You must be an Aide to terminate sessions.\n",
734                         ERROR+HIGHER_ACCESS_REQUIRED);
735                 return;
736                 }
737
738         session_num = extract_int(cmdbuf, 0);
739         if (session_num == CC->cs_pid) {
740                 cprintf("%d You can't kill your own session.\n", ERROR);
741                 return;
742                 }
743
744         lprintf(9, "Locating session to kill\n");
745         begin_critical_section(S_SESSION_TABLE);
746         for (ccptr = ContextList; ccptr != NULL; ccptr = ccptr->next) {
747                 if (session_num == ccptr->cs_pid) {
748                         ccptr->kill_me = 1;
749                         found_it = 1;
750                         }
751                 }
752         end_critical_section(S_SESSION_TABLE);
753
754         if (found_it) {
755                 cprintf("%d Session terminated.\n", OK);
756                 }
757         else {
758                 cprintf("%d No such session.\n", ERROR);
759                 }
760         }
761
762
763
764
765
766 /* 
767  * get the paginator prompt
768  */
769 void cmd_more(void) {
770         cprintf("%d %s\n",OK,config.c_moreprompt);
771         }
772
773 /*
774  * echo 
775  */
776 void cmd_echo(char *etext)
777 {
778         cprintf("%d %s\n",OK,etext);
779         }
780
781
782
783 /* 
784  * identify as internal program
785  */
786 void cmd_ipgm(char *argbuf)
787 {
788         int secret;
789
790         secret = extract_int(argbuf, 0);
791         if (secret == config.c_ipgm_secret) {
792                 CC->internal_pgm = 1;
793                 strcpy(CC->curr_user, "<internal program>");
794                 CC->cs_flags = CC->cs_flags|CS_STEALTH;
795                 cprintf("%d Authenticated as an internal program.\n",OK);
796                 }
797         else {
798                 cprintf("%d Authentication failed.\n",ERROR);
799                 lprintf(3, "Warning: ipgm authentication failed.\n");
800                 }
801         }
802
803
804 /*
805  * Shut down the server
806  */
807 void cmd_down(void) {
808         if (!CC->logged_in) {
809                 cprintf("%d Not logged in.\n", ERROR+NOT_LOGGED_IN);
810                 return;
811                 }
812
813         if (CC->usersupp.axlevel < 6) {
814                 cprintf("%d You must be an Aide to shut down the server.\n",
815                         ERROR+HIGHER_ACCESS_REQUIRED);
816                 return;
817                 }
818
819         cprintf("%d Shutting down server.  Goodbye.\n", OK);
820         master_cleanup();
821         }
822
823 /*
824  * Schedule or cancel a server shutdown
825  */
826 void cmd_scdn(char *argbuf)
827 {
828         int new_state;
829
830         if (!CC->logged_in) {
831                 cprintf("%d Not logged in.\n",ERROR+NOT_LOGGED_IN);
832                 return;
833                 }
834
835         if (CC->usersupp.axlevel < 6) {
836                 cprintf("%d You must be an Aide to schedule a shutdown.\n",
837                         ERROR+HIGHER_ACCESS_REQUIRED);
838                 return;
839                 }
840
841         new_state = extract_int(argbuf, 0);
842         if ((new_state == 0) || (new_state == 1)) {
843                 ScheduledShutdown = new_state;
844                 }
845         cprintf("%d %d\n", OK, ScheduledShutdown);
846         }
847
848
849 /*
850  * Back-end function for starting a session
851  */
852 void begin_session(struct CitContext *con)
853 {
854         int len;
855         struct sockaddr_in sin;
856
857         /* 
858          * Initialize some variables specific to our context.
859          */
860         con->logged_in = 0;
861         con->internal_pgm = 0;
862         con->download_fp = NULL;
863         con->upload_fp = NULL;
864         con->FirstExpressMessage = NULL;
865         time(&con->lastcmd);
866         time(&con->lastidle);
867         strcpy(con->lastcmdname, "    ");
868         strcpy(con->cs_clientname, "(unknown)");
869         strcpy(con->curr_user,"(not logged in)");
870         strcpy(con->net_node,"");
871         snprintf(con->temp, sizeof con->temp, tmpnam(NULL));
872         safestrncpy(con->cs_host, config.c_fqdn, sizeof con->cs_host);
873         con->cs_host[sizeof con->cs_host - 1] = 0;
874         len = sizeof sin;
875         if (!getpeername(con->client_socket, (struct sockaddr *) &sin, &len))
876                 locate_host(con->cs_host, &sin.sin_addr);
877         con->cs_flags = 0;
878         con->upload_type = UPL_FILE;
879         con->dl_is_net = 0;
880         con->FirstSessData = NULL;
881
882         con->nologin = 0;
883         if ((config.c_maxsessions > 0)&&(num_sessions > config.c_maxsessions))
884                 con->nologin = 1;
885
886         lprintf(3, "citserver[%3d]: started.\n", con->cs_pid);
887
888         /* Run any session startup routines registered by loadable modules */
889         PerformSessionHooks(EVT_START);
890
891         rec_log(CL_CONNECT, "");
892 }
893
894
895 void citproto_begin_session() {
896         if (CC->nologin==1) {
897                 cprintf("%d %s: Too many users are already online "
898                         "(maximum is %d)\n",
899                         ERROR+MAX_SESSIONS_EXCEEDED,
900                         config.c_nodename, config.c_maxsessions);
901                 }
902         else {
903                 cprintf("%d %s Citadel/UX server ready.\n",
904                         OK, config.c_nodename);
905                 }
906 }
907
908
909
910
911 /*
912  * This loop recognizes all server commands.
913  */
914 void do_command_loop(void) {
915         char cmdbuf[256];
916
917         time(&CC->lastcmd);
918         memset(cmdbuf, 0, sizeof cmdbuf); /* Clear it, just in case */
919         if (client_gets(cmdbuf) < 1) {
920                 lprintf(3, "Client socket is broken.  Ending session.\n");
921                 CC->kill_me = 1;
922                 return;
923         }
924         lprintf(5, "citserver[%3d]: %s\n", CC->cs_pid, cmdbuf);
925
926         /*
927          * Let other clients see the last command we executed, and
928          * update the idle time, but not NOOP, PEXP, or GEXP.
929          */
930         if ( (strncasecmp(cmdbuf, "NOOP", 4))
931            && (strncasecmp(cmdbuf, "PEXP", 4))
932            && (strncasecmp(cmdbuf, "GEXP", 4)) ) {
933                 strcpy(CC->lastcmdname, "    ");
934                 safestrncpy(CC->lastcmdname, cmdbuf, 
935                         sizeof(CC->lastcmdname) );
936                 time(&CC->lastidle);
937                 }
938                 
939         if ((strncasecmp(cmdbuf, "ENT0", 4))
940            && (strncasecmp(cmdbuf, "MESG", 4))
941            && (strncasecmp(cmdbuf, "MSGS", 4)))
942         {
943            CC->cs_flags &= ~CS_POSTING;
944         }
945                    
946         if (!strncasecmp(cmdbuf,"NOOP",4)) {
947                 cprintf("%d%cok\n",OK,check_express());
948                 }
949
950         else if (!strncasecmp(cmdbuf,"QUIT",4)) {
951                 cprintf("%d Goodbye.\n",OK);
952                 CC->kill_me = 1;
953                 }
954
955         else if (!strncasecmp(cmdbuf,"LOUT",4)) {
956                 if (CC->logged_in) logout(CC);
957                 cprintf("%d logged out.\n",OK);
958                 }
959
960         else if (!strncasecmp(cmdbuf,"USER",4)) {
961                 cmd_user(&cmdbuf[5]);
962                 }
963
964         else if (!strncasecmp(cmdbuf,"PASS",4)) {
965                 cmd_pass(&cmdbuf[5]);
966                 }
967
968         else if (!strncasecmp(cmdbuf,"NEWU",4)) {
969                 cmd_newu(&cmdbuf[5]);
970                 }
971
972         else if (!strncasecmp(cmdbuf,"SETP",4)) {
973                 cmd_setp(&cmdbuf[5]);
974                 }
975
976         else if (!strncasecmp(cmdbuf,"LRMS",4)) {
977                 cmd_lrms(&cmdbuf[5]);
978                 }
979
980         else if (!strncasecmp(cmdbuf,"LKRA",4)) {
981                 cmd_lkra(&cmdbuf[5]);
982                 }
983
984         else if (!strncasecmp(cmdbuf,"LKRN",4)) {
985                 cmd_lkrn(&cmdbuf[5]);
986                 }
987
988         else if (!strncasecmp(cmdbuf,"LKRO",4)) {
989                 cmd_lkro(&cmdbuf[5]);
990                 }
991
992         else if (!strncasecmp(cmdbuf,"LZRM",4)) {
993                 cmd_lzrm(&cmdbuf[5]);
994                 }
995
996         else if (!strncasecmp(cmdbuf,"GETU",4)) {
997                 cmd_getu();
998                 }
999
1000         else if (!strncasecmp(cmdbuf,"SETU",4)) {
1001                 cmd_setu(&cmdbuf[5]);
1002                 }
1003
1004         else if (!strncasecmp(cmdbuf,"GOTO",4)) {
1005                 cmd_goto(&cmdbuf[5]);
1006                 }
1007
1008         else if (!strncasecmp(cmdbuf,"MSGS",4)) {
1009                 cmd_msgs(&cmdbuf[5]);
1010                 }
1011
1012         else if (!strncasecmp(cmdbuf,"WHOK",4)) {
1013                 cmd_whok();
1014                 }
1015
1016         else if (!strncasecmp(cmdbuf,"RDIR",4)) {
1017                 cmd_rdir();
1018                 }
1019
1020         else if (!strncasecmp(cmdbuf,"MSG0",4)) {
1021                 cmd_msg0(&cmdbuf[5]);
1022                 }
1023
1024         else if (!strncasecmp(cmdbuf,"MSG2",4)) {
1025                 cmd_msg2(&cmdbuf[5]);
1026                 }
1027
1028         else if (!strncasecmp(cmdbuf,"MSG3",4)) {
1029                 cmd_msg3(&cmdbuf[5]);
1030                 }
1031
1032         else if (!strncasecmp(cmdbuf,"MSG4",4)) {
1033                 cmd_msg4(&cmdbuf[5]);
1034                 }
1035
1036         else if (!strncasecmp(cmdbuf,"OPNA",4)) {
1037                 cmd_opna(&cmdbuf[5]);
1038                 }
1039
1040         else if (!strncasecmp(cmdbuf,"INFO",4)) {
1041                 cmd_info();
1042                 }
1043
1044         else if (!strncasecmp(cmdbuf,"SLRP",4)) {
1045                 cmd_slrp(&cmdbuf[5]);
1046                 }
1047
1048         else if (!strncasecmp(cmdbuf,"INVT",4)) {
1049                 cmd_invt_kick(&cmdbuf[5],1);
1050                 }
1051
1052         else if (!strncasecmp(cmdbuf,"KICK",4)) {
1053                 cmd_invt_kick(&cmdbuf[5],0);
1054                 }
1055
1056         else if (!strncasecmp(cmdbuf,"GETR",4)) {
1057                 cmd_getr();
1058                 }
1059
1060         else if (!strncasecmp(cmdbuf,"SETR",4)) {
1061                 cmd_setr(&cmdbuf[5]);
1062                 }
1063
1064         else if (!strncasecmp(cmdbuf,"GETA",4)) {
1065                 cmd_geta();
1066                 }
1067
1068         else if (!strncasecmp(cmdbuf,"SETA",4)) {
1069                 cmd_seta(&cmdbuf[5]);
1070                 }
1071
1072         else if (!strncasecmp(cmdbuf,"ENT0",4)) {
1073                 cmd_ent0(&cmdbuf[5]);
1074                 }
1075
1076         else if (!strncasecmp(cmdbuf,"ENT3",4)) {
1077                 cmd_ent3(&cmdbuf[5]);
1078                 }
1079
1080         else if (!strncasecmp(cmdbuf,"RINF",4)) {
1081                 cmd_rinf();
1082                 }
1083
1084         else if (!strncasecmp(cmdbuf,"DELE",4)) {
1085                 cmd_dele(&cmdbuf[5]);
1086                 }
1087
1088         else if (!strncasecmp(cmdbuf,"KILL",4)) {
1089                 cmd_kill(&cmdbuf[5]);
1090                 }
1091
1092         else if (!strncasecmp(cmdbuf,"CRE8",4)) {
1093                 cmd_cre8(&cmdbuf[5]);
1094                 }
1095
1096         else if (!strncasecmp(cmdbuf,"MOVE",4)) {
1097                 cmd_move(&cmdbuf[5]);
1098                 }
1099
1100         else if (!strncasecmp(cmdbuf,"FORG",4)) {
1101                 cmd_forg();
1102                 }
1103
1104         else if (!strncasecmp(cmdbuf,"MESG",4)) {
1105                 cmd_mesg(&cmdbuf[5]);
1106                 }
1107
1108         else if (!strncasecmp(cmdbuf,"EMSG",4)) {
1109                 cmd_emsg(&cmdbuf[5]);
1110                 }
1111
1112         else if (!strncasecmp(cmdbuf,"GNUR",4)) {
1113                 cmd_gnur();
1114                 }
1115
1116         else if (!strncasecmp(cmdbuf,"VALI",4)) {
1117                 cmd_vali(&cmdbuf[5]);
1118                 }
1119
1120         else if (!strncasecmp(cmdbuf,"EINF",4)) {
1121                 cmd_einf(&cmdbuf[5]);
1122                 }
1123
1124         else if (!strncasecmp(cmdbuf,"LIST",4)) {
1125                 cmd_list();
1126                 }
1127
1128         else if (!strncasecmp(cmdbuf,"CHEK",4)) {
1129                 cmd_chek();
1130                 }
1131
1132         else if (!strncasecmp(cmdbuf,"DELF",4)) {
1133                 cmd_delf(&cmdbuf[5]);
1134                 }
1135
1136         else if (!strncasecmp(cmdbuf,"MOVF",4)) {
1137                 cmd_movf(&cmdbuf[5]);
1138                 }
1139
1140         else if (!strncasecmp(cmdbuf,"NETF",4)) {
1141                 cmd_netf(&cmdbuf[5]);
1142                 }
1143
1144         else if (!strncasecmp(cmdbuf,"RWHO",4)) {
1145                 cmd_rwho();
1146                 }
1147
1148         else if (!strncasecmp(cmdbuf,"OPEN",4)) {
1149                 cmd_open(&cmdbuf[5]);
1150                 }
1151
1152         else if (!strncasecmp(cmdbuf,"CLOS",4)) {
1153                 cmd_clos();
1154                 }
1155
1156         else if (!strncasecmp(cmdbuf,"UOPN",4)) {
1157                 cmd_uopn(&cmdbuf[5]);
1158                 }
1159
1160         else if (!strncasecmp(cmdbuf,"UCLS",4)) {
1161                 cmd_ucls(&cmdbuf[5]);
1162                 }
1163
1164         else if (!strncasecmp(cmdbuf,"READ",4)) {
1165                 cmd_read(&cmdbuf[5]);
1166                 }
1167
1168         else if (!strncasecmp(cmdbuf,"WRIT",4)) {
1169                 cmd_writ(&cmdbuf[5]);
1170                 }
1171
1172         else if (!strncasecmp(cmdbuf,"QUSR",4)) {
1173                 cmd_qusr(&cmdbuf[5]);
1174                 }
1175
1176         else if (!strncasecmp(cmdbuf,"ECHO",4)) {
1177                 cmd_echo(&cmdbuf[5]);
1178                 }
1179
1180         else if (!strncasecmp(cmdbuf,"OIMG",4)) {
1181                 cmd_oimg(&cmdbuf[5]);
1182                 }
1183
1184         else if (!strncasecmp(cmdbuf,"MORE",4)) {
1185                 cmd_more();
1186                 }
1187
1188         else if (!strncasecmp(cmdbuf,"NETP",4)) {
1189                 cmd_netp(&cmdbuf[5]);
1190                 }
1191
1192         else if (!strncasecmp(cmdbuf,"NDOP",4)) {
1193                 cmd_ndop(&cmdbuf[5]);
1194                 }
1195
1196         else if (!strncasecmp(cmdbuf,"NUOP",4)) {
1197                 cmd_nuop(&cmdbuf[5]);
1198                 }
1199
1200         else if (!strncasecmp(cmdbuf,"LFLR",4)) {
1201                 cmd_lflr();
1202                 }
1203
1204         else if (!strncasecmp(cmdbuf,"CFLR",4)) {
1205                 cmd_cflr(&cmdbuf[5]);
1206                 }
1207
1208         else if (!strncasecmp(cmdbuf,"KFLR",4)) {
1209                 cmd_kflr(&cmdbuf[5]);
1210                 }
1211
1212         else if (!strncasecmp(cmdbuf,"EFLR",4)) {
1213                 cmd_eflr(&cmdbuf[5]);
1214                 }
1215
1216         else if (!strncasecmp(cmdbuf,"IDEN",4)) {
1217                 cmd_iden(&cmdbuf[5]);
1218                 }
1219
1220         else if (!strncasecmp(cmdbuf,"IPGM",4)) {
1221                 cmd_ipgm(&cmdbuf[5]);
1222                 }
1223
1224         else if (!strncasecmp(cmdbuf,"EBIO",4)) {
1225                 cmd_ebio();
1226                 }
1227
1228         else if (!strncasecmp(cmdbuf,"RBIO",4)) {
1229                 cmd_rbio(&cmdbuf[5]);
1230                 }
1231
1232         else if (!strncasecmp(cmdbuf,"LBIO",4)) {
1233                 cmd_lbio();
1234                 }
1235
1236         else if (!strncasecmp(cmdbuf,"STEL",4)) {
1237                 cmd_stel(&cmdbuf[5]);
1238                 }
1239
1240         else if (!strncasecmp(cmdbuf,"TERM",4)) {
1241                 cmd_term(&cmdbuf[5]);
1242                 }
1243
1244         else if (!strncasecmp(cmdbuf,"DOWN",4)) {
1245                 cmd_down();
1246                 }
1247
1248         else if (!strncasecmp(cmdbuf,"SCDN",4)) {
1249                 cmd_scdn(&cmdbuf[5]);
1250                 }
1251
1252         else if (!strncasecmp(cmdbuf, "NSET", 4)) {
1253                 cmd_nset(&cmdbuf[5]);
1254                 }
1255
1256         else if (!strncasecmp(cmdbuf, "UIMG", 4)) {
1257                 cmd_uimg(&cmdbuf[5]);
1258                 }
1259
1260         else if (!strncasecmp(cmdbuf, "UCHG", 4)) {
1261                 cmd_uchg(&cmdbuf[5]);
1262                 }
1263
1264         else if (!strncasecmp(cmdbuf, "TIME", 4)) {
1265                 cmd_time();
1266                 }
1267
1268         else if (!strncasecmp(cmdbuf, "HCHG", 4)) {
1269                 cmd_hchg(&cmdbuf[5]);
1270                 }
1271
1272         else if (!strncasecmp(cmdbuf, "RCHG", 4)) {
1273                 cmd_rchg(&cmdbuf[5]);
1274                 }
1275
1276         else if (!strncasecmp(cmdbuf, "AGUP", 4)) {
1277                 cmd_agup(&cmdbuf[5]);
1278                 }
1279
1280         else if (!strncasecmp(cmdbuf, "ASUP", 4)) {
1281                 cmd_asup(&cmdbuf[5]);
1282                 }
1283
1284         else if (!strncasecmp(cmdbuf, "GPEX", 4)) {
1285                 cmd_gpex(&cmdbuf[5]);
1286                 }
1287
1288         else if (!strncasecmp(cmdbuf, "SPEX", 4)) {
1289                 cmd_spex(&cmdbuf[5]);
1290                 }
1291
1292         else if (!strncasecmp(cmdbuf, "CONF", 4)) {
1293                 cmd_conf(&cmdbuf[5]);
1294                 }
1295
1296 #ifdef DEBUG_MEMORY_LEAKS
1297         else if (!strncasecmp(cmdbuf, "LEAK", 4)) {
1298                 dump_tracked();
1299                 }
1300 #endif
1301
1302         else if (!DLoader_Exec_Cmd(cmdbuf))
1303                 {
1304                    cprintf("%d Unrecognized or unsupported command.\n",
1305                             ERROR);
1306                 }
1307
1308         /* Run any after-each-command outines registered by modules */
1309         PerformSessionHooks(EVT_CMD);
1310 }