* added pid file writing
[citadel.git] / citadel / citserver.c
1 /* 
2  * $Id$
3  *
4  * Main source module for the Citadel server
5  *
6  */
7
8 #ifdef DLL_EXPORT
9 #define IN_LIBCIT
10 #endif
11
12 #include "sysdep.h"
13 #include <stdlib.h>
14 #include <unistd.h>
15 #include <stdio.h>
16 #include <fcntl.h>
17 #include <signal.h>
18 #include <sys/types.h>
19 #include <sys/stat.h>
20
21
22 #if TIME_WITH_SYS_TIME
23 # include <sys/time.h>
24 # include <time.h>
25 #else
26 # if HAVE_SYS_TIME_H
27 #  include <sys/time.h>
28 # else
29 #  include <time.h>
30 # endif
31 #endif
32
33 #include <ctype.h>
34 #include <string.h>
35 #include <errno.h>
36 #include <limits.h>
37 /* #include <dlfcn.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 "citadel.h"
44 #include "server.h"
45 #include "serv_extensions.h"
46 #include "sysdep_decls.h"
47 #include "citserver.h"
48 #include "config.h"
49 #include "database.h"
50 #include "housekeeping.h"
51 #include "user_ops.h"
52 #include "msgbase.h"
53 #include "support.h"
54 #include "locate_host.h"
55 #include "room_ops.h"
56 #include "file_ops.h"
57 #include "policy.h"
58 #include "control.h"
59 #include "tools.h"
60
61 #ifndef HAVE_SNPRINTF
62 #include "snprintf.h"
63 #endif
64
65 struct CitContext *ContextList = NULL;
66 struct CitContext* next_session = NULL;
67 char *unique_session_numbers;
68 int ScheduledShutdown = 0;
69 int do_defrag = 0;
70 time_t server_startup_time;
71 char pid_file_name[PATH_MAX];
72
73 /*
74  * Various things that need to be initialized at startup
75  */
76 void master_startup(void) {
77         struct timeval tv;
78         unsigned int seed;
79         FILE *urandom;
80         struct ctdlroom qrbuf;
81         FILE *pidfile_fp;
82         
83         lprintf(CTDL_DEBUG, "master_startup() started\n");
84         time(&server_startup_time);
85
86         /* pid file.  If we go FSSTND this should end up in 'localstatedir' */
87         snprintf(pid_file_name, sizeof pid_file_name, "./citadel.pid");
88         pidfile_fp = fopen(pid_file_name, "w");
89         if (pidfile_fp != NULL) {
90                 fprintf(pidfile_fp, "%d\n", (int)getpid());
91                 fclose(pidfile_fp);
92         }
93
94         lprintf(CTDL_INFO, "Opening databases\n");
95         open_databases();
96
97         if (do_defrag) {
98                 defrag_databases();
99         }
100
101         check_ref_counts();
102
103         lprintf(CTDL_INFO, "Creating base rooms (if necessary)\n");
104         create_room(BASEROOM,           0, "", 0, 1, 0, VIEW_BBS);
105         create_room(AIDEROOM,           3, "", 0, 1, 0, VIEW_BBS);
106         create_room(SYSCONFIGROOM,      3, "", 0, 1, 0, VIEW_BBS);
107         create_room(config.c_twitroom,  0, "", 0, 1, 0, VIEW_BBS);
108
109         /* The "Local System Configuration" room doesn't need to be visible */
110         if (lgetroom(&qrbuf, SYSCONFIGROOM) == 0) {
111                 qrbuf.QRflags2 |= QR2_SYSTEM;
112                 lputroom(&qrbuf);
113         }
114
115         lprintf(CTDL_INFO, "Seeding the pseudo-random number generator...\n");
116         urandom = fopen("/dev/urandom", "r");
117         if (urandom != NULL) {
118                 fread(&seed, sizeof seed, 1, urandom);
119                 fclose(urandom);
120         }
121         else {
122                 gettimeofday(&tv, NULL);
123                 seed = tv.tv_usec;
124         }
125         srandom(seed);
126
127         lprintf(CTDL_INFO, "Initializing ipgm secret\n");
128         get_config();
129         config.c_ipgm_secret = rand();
130         put_config();
131
132         lprintf(CTDL_DEBUG, "master_startup() finished\n");
133 }
134
135
136 /*
137  * Cleanup routine to be called when the server is shutting down.
138  */
139 void master_cleanup(int exitcode) {
140         struct CleanupFunctionHook *fcn;
141         static int already_cleaning_up = 0;
142
143         if (already_cleaning_up) while(1) sleep(1);
144         already_cleaning_up = 1;
145
146         /* Run any cleanup routines registered by loadable modules */
147         for (fcn = CleanupHookTable; fcn != NULL; fcn = fcn->next) {
148                 (*fcn->h_function_pointer)();
149         }
150
151         /* Close databases */
152         lprintf(CTDL_INFO, "Closing databases\n");
153         close_databases();
154
155         /* Do system-dependent stuff */
156         sysdep_master_cleanup();
157
158 #ifdef DEBUG_MEMORY_LEAKS
159         dump_heap();
160 #endif
161
162         /* Now go away. */
163         lprintf(CTDL_NOTICE, "citserver: Exiting with status %d\n", exitcode);
164         fflush(stdout); fflush(stderr);
165
166         unlink(pid_file_name);
167         exit(exitcode);
168 }
169
170
171 /*
172  * Free any per-session data allocated by modules or whatever
173  */
174 void deallocate_user_data(struct CitContext *con)
175 {
176         struct CtdlSessData *ptr;
177
178         begin_critical_section(S_SESSION_TABLE);
179         while (con->FirstSessData != NULL) {
180                 lprintf(CTDL_DEBUG, "Deallocating user data symbol %ld\n",
181                         con->FirstSessData->sym_id);
182                 if (con->FirstSessData->sym_data != NULL)
183                         free(con->FirstSessData->sym_data);
184                 ptr = con->FirstSessData->next;
185                 free(con->FirstSessData);
186                 con->FirstSessData = ptr;
187         }
188         end_critical_section(S_SESSION_TABLE);
189 }
190
191
192
193
194 /*
195  * Terminate a session and remove its context data structure.
196  */
197 void RemoveContext (struct CitContext *con)
198 {
199         if (con==NULL) {
200                 lprintf(CTDL_ERR, "WARNING: RemoveContext() called with NULL!\n");
201                 return;
202         }
203         lprintf(CTDL_DEBUG, "RemoveContext() called\n");
204
205         /* Remove the context from the global context list.  This needs
206          * to get done FIRST to avoid concurrency problems.  It is *vitally*
207          * important to keep num_sessions accurate!!
208          */
209         lprintf(CTDL_DEBUG, "Removing context for session %d\n", con->cs_pid);
210         begin_critical_section(S_SESSION_TABLE);
211           if (con->prev) con->prev->next = con->next; else ContextList = con->next;
212           if (con->next) con->next->prev = con->prev;
213           --num_sessions;
214         end_critical_section(S_SESSION_TABLE);
215
216         /* Run any cleanup routines registered by loadable modules.
217          * Note 1: This must occur *before* deallocate_user_data() because the
218          *         cleanup functions might touch dynamic session data.
219          * Note 2: We have to "become_session()" because the cleanup functions
220          *         might make references to "CC" assuming it's the right one.
221          */
222         become_session(con);
223         PerformSessionHooks(EVT_STOP);
224         become_session(NULL);
225
226         /* Now handle all of the administrivia. */
227         lprintf(CTDL_DEBUG, "Calling logout(%d)\n", con->cs_pid);
228         logout(con);
229
230         unlink(con->temp);
231         lprintf(CTDL_NOTICE, "[%3d] Session ended.\n", con->cs_pid);
232
233         /* Deallocate any user-data attached to this session */
234         deallocate_user_data(con);
235
236         /* If the client is still connected, blow 'em away. */
237         lprintf(CTDL_DEBUG, "Closing socket %d\n", con->client_socket);
238         close(con->client_socket);
239
240         /* This is where we used to check for scheduled shutdowns. */
241
242         /* Free up the memory used by this context */
243         free(con);
244
245         lprintf(CTDL_DEBUG, "Done with RemoveContext()\n");
246 }
247
248
249
250
251
252 /*
253  * Return a pointer to some generic per-session user data.
254  * (This function returns NULL if the requested symbol is not allocated.)
255  *
256  * NOTE: we use critical sections for allocating and de-allocating these,
257  *       but not for locating one.
258  */
259 void *CtdlGetUserData(unsigned long requested_sym) 
260 {
261         struct CtdlSessData *ptr;
262
263         for (ptr = CC->FirstSessData; ptr != NULL; ptr = ptr->next)
264                 if (ptr->sym_id == requested_sym)
265                         return(ptr->sym_data);
266
267         lprintf(CTDL_ERR, "ERROR! CtdlGetUserData(%ld) symbol not allocated\n",
268                 requested_sym);
269         return NULL;
270 }
271
272
273 /*
274  * Allocate some generic per-session user data.
275  */
276 void CtdlAllocUserData(unsigned long requested_sym, size_t num_bytes)
277 {
278         struct CtdlSessData *ptr;
279
280         lprintf(CTDL_DEBUG, "CtdlAllocUserData(%ld) called\n", requested_sym);
281
282         /* Fail silently if the symbol is already registered. */
283         for (ptr = CC->FirstSessData; ptr != NULL; ptr = ptr->next)  {
284                 if (ptr->sym_id == requested_sym) {
285                         return;
286                 }
287         }
288
289         /* Grab us some memory!  Dem's good eatin' !!  */
290         ptr = malloc(sizeof(struct CtdlSessData));
291         ptr->sym_id = requested_sym;
292         ptr->sym_data = malloc(num_bytes);
293         memset(ptr->sym_data, 0, num_bytes);
294
295         begin_critical_section(S_SESSION_TABLE);
296         ptr->next = CC->FirstSessData;
297         CC->FirstSessData = ptr;
298         end_critical_section(S_SESSION_TABLE);
299
300         lprintf(CTDL_DEBUG, "CtdlAllocUserData(%ld) finished\n", requested_sym);
301 }
302
303
304 /* 
305  * Change the size of a buffer allocated with CtdlAllocUserData()
306  */
307 void CtdlReallocUserData(unsigned long requested_sym, size_t num_bytes)
308 {
309         struct CtdlSessData *ptr;
310
311         for (ptr = CC->FirstSessData; ptr != NULL; ptr = ptr->next)  {
312                 if (ptr->sym_id == requested_sym) {
313                         ptr->sym_data = realloc(ptr->sym_data, num_bytes);
314                         return;
315                 }
316         }
317
318         lprintf(CTDL_ERR, "CtdlReallocUserData() ERROR: symbol %ld not found!\n",
319                 requested_sym);
320 }
321
322
323
324
325
326
327 /*
328  * cmd_info()  -  tell the client about this server
329  */
330 void cmd_info(void) {
331         cprintf("%d Server info:\n", LISTING_FOLLOWS);
332         cprintf("%d\n", CC->cs_pid);
333         cprintf("%s\n", config.c_nodename);
334         cprintf("%s\n", config.c_humannode);
335         cprintf("%s\n", config.c_fqdn);
336         cprintf("%s\n", CITADEL);
337         cprintf("%d\n", REV_LEVEL);
338         cprintf("%s\n", config.c_bbs_city);
339         cprintf("%s\n", config.c_sysadm);
340         cprintf("%d\n", SERVER_TYPE);
341         cprintf("%s\n", config.c_moreprompt);
342         cprintf("1\n"); /* 1 = yes, this system supports floors */
343         cprintf("1\n"); /* 1 = we support the extended paging options */
344         cprintf("%s\n", CC->cs_nonce);
345         cprintf("1\n"); /* 1 = yes, this system supports the QNOP command */
346 #ifdef HAVE_LDAP
347         cprintf("1\n"); /* 1 = yes, this server is LDAP-enabled */
348 #else
349         cprintf("0\n"); /* 1 = no, this server is not LDAP-enabled */
350 #endif
351         cprintf("000\n");
352 }
353
354
355 /*
356  * returns an asterisk if there are any instant messages waiting,
357  * space otherwise.
358  */
359 char CtdlCheckExpress(void) {
360         if (CC->FirstExpressMessage == NULL) {
361                 return(' ');
362         }
363         else {
364                 return('*');
365         }
366 }
367
368 void cmd_time(void)
369 {
370    time_t tv;
371    struct tm tmp;
372    
373    tv = time(NULL);
374    localtime_r(&tv, &tmp);
375    
376    /* timezone and daylight global variables are not portable. */
377 #ifdef HAVE_STRUCT_TM_TM_GMTOFF
378    cprintf("%d %ld|%ld|%d\n", CIT_OK, (long)tv, tmp.tm_gmtoff, tmp.tm_isdst);
379 #else
380    cprintf("%d %ld|%ld|%d\n", CIT_OK, (long)tv, timezone, tmp.tm_isdst);
381 #endif
382 }
383
384
385 /*
386  * Check originating host against the public_clients file.  This determines
387  * whether the client is allowed to change the hostname for this session
388  * (for example, to show the location of the user rather than the location
389  * of the client).
390  */
391 int is_public_client(void)
392 {
393         char buf[SIZ];
394         char addrbuf[SIZ];
395         FILE *fp;
396         int i;
397         struct stat statbuf;
398         static time_t pc_timestamp = 0;
399         static char public_clients[SIZ];
400
401 #define PUBLIC_CLIENTS "./public_clients"
402
403         /*
404          * Check the time stamp on the public_clients file.  If it's been
405          * updated since the last time we were here (or if this is the first
406          * time we've been through the loop), read its contents and learn
407          * the IP addresses of the listed hosts.
408          */
409         if (stat(PUBLIC_CLIENTS, &statbuf) != 0) {
410                 /* No public_clients file exists, so bail out */
411                 lprintf(CTDL_WARNING, "Warning: '%s' does not exist\n", PUBLIC_CLIENTS);
412                 return(0);
413         }
414
415         if (statbuf.st_mtime > pc_timestamp) {
416                 begin_critical_section(S_PUBLIC_CLIENTS);
417                 lprintf(CTDL_INFO, "Loading %s\n", PUBLIC_CLIENTS);
418
419                 strcpy(public_clients, "127.0.0.1");
420                 if (hostname_to_dotted_quad(addrbuf, config.c_fqdn) == 0) {
421                         strcat(public_clients, "|");
422                         strcat(public_clients, addrbuf);
423                 }
424
425                 fp = fopen("public_clients", "r");
426                 if (fp != NULL) while (fgets(buf, sizeof buf, fp)!=NULL) {
427                         for (i=0; i<strlen(buf); ++i) {
428                                 if (buf[i] == '#') buf[i] = 0;
429                         }
430                         while (isspace((buf[strlen(buf)-1]))) {
431                                 buf[strlen(buf)-1] = 0;
432                         }
433                         if (hostname_to_dotted_quad(addrbuf, buf) == 0) {
434                                 if ((strlen(public_clients) +
435                                    strlen(addrbuf) + 2)
436                                    < sizeof(public_clients)) {
437                                         strcat(public_clients, addrbuf);
438                                 }
439                         }
440                 }
441                 fclose(fp);
442                 pc_timestamp = time(NULL);
443                 end_critical_section(S_PUBLIC_CLIENTS);
444         }
445
446         lprintf(CTDL_DEBUG, "Checking whether %s is a local or public client\n",
447                 CC->cs_addr);
448         for (i=0; i<num_parms(public_clients); ++i) {
449                 extract(addrbuf, public_clients, i);
450                 if (!strcasecmp(CC->cs_addr, addrbuf)) {
451                         lprintf(CTDL_DEBUG, "... yes it is.\n");
452                         return(1);
453                 }
454         }
455
456         /* No hits.  This is not a public client. */
457         lprintf(CTDL_DEBUG, "... no it isn't.\n");
458         return(0);
459 }
460
461
462 /*
463  * the client is identifying itself to the server
464  */
465 void cmd_iden(char *argbuf)
466 {
467         int dev_code;
468         int cli_code;
469         int rev_level;
470         char desc[SIZ];
471         char from_host[SIZ];
472         struct in_addr addr;
473         int do_lookup = 0;
474
475         if (num_parms(argbuf)<4) {
476                 cprintf("%d usage error\n", ERROR + ILLEGAL_VALUE);
477                 return;
478         }
479
480         dev_code = extract_int(argbuf,0);
481         cli_code = extract_int(argbuf,1);
482         rev_level = extract_int(argbuf,2);
483         extract(desc,argbuf,3);
484
485         safestrncpy(from_host, config.c_fqdn, sizeof from_host);
486         from_host[sizeof from_host - 1] = 0;
487         if (num_parms(argbuf)>=5) extract(from_host,argbuf,4);
488
489         CC->cs_clientdev = dev_code;
490         CC->cs_clienttyp = cli_code;
491         CC->cs_clientver = rev_level;
492         safestrncpy(CC->cs_clientname, desc, sizeof CC->cs_clientname);
493         CC->cs_clientname[31] = 0;
494
495         if (strlen(from_host) > 0) {
496                 if (CC->is_local_socket) do_lookup = 1;
497                 else if (is_public_client()) do_lookup = 1;
498         }
499
500         if (do_lookup) {
501                 lprintf(CTDL_DEBUG, "Looking up hostname '%s'\n", from_host);
502                 if ((addr.s_addr = inet_addr(from_host)) != -1) {
503                         locate_host(CC->cs_host, sizeof CC->cs_host,
504                                 NULL, 0,
505                                 &addr);
506                 }
507                 else {
508                         safestrncpy(CC->cs_host, from_host, sizeof CC->cs_host);
509                         CC->cs_host[sizeof CC->cs_host - 1] = 0;
510                 }
511         }
512
513         lprintf(CTDL_NOTICE, "Client %d/%d/%01d.%02d (%s) from %s\n",
514                 dev_code,
515                 cli_code,
516                 (rev_level / 100),
517                 (rev_level % 100),
518                 desc,
519                 CC->cs_host);
520         cprintf("%d Ok\n",CIT_OK);
521 }
522
523
524 /*
525  * display system messages or help
526  */
527 void cmd_mesg(char *mname)
528 {
529         FILE *mfp;
530         char targ[SIZ];
531         char buf[SIZ];
532         char buf2[SIZ];
533         char *dirs[2];
534
535         extract(buf,mname,0);
536
537         dirs[0]=malloc(64);
538         dirs[1]=malloc(64);
539         strcpy(dirs[0],"messages");
540         strcpy(dirs[1],"help");
541         snprintf(buf2, sizeof buf2, "%s.%d.%d", buf, CC->cs_clientdev, CC->cs_clienttyp);
542         mesg_locate(targ,sizeof targ,buf2,2,(const char **)dirs);
543         if (strlen(targ) == 0) {
544                 snprintf(buf2, sizeof buf2, "%s.%d", buf, CC->cs_clientdev);
545                 mesg_locate(targ,sizeof targ,buf2,2,(const char **)dirs);
546                 if (strlen(targ) == 0) {
547                         mesg_locate(targ,sizeof targ,buf,2,(const char **)dirs);
548                 }       
549         }
550         free(dirs[0]);
551         free(dirs[1]);
552
553         if (strlen(targ)==0) {
554                 cprintf("%d '%s' not found.\n",ERROR + FILE_NOT_FOUND, mname);
555                 return;
556         }
557
558         mfp = fopen(targ,"r");
559         if (mfp==NULL) {
560                 cprintf("%d Cannot open '%s': %s\n",
561                         ERROR + INTERNAL_ERROR, targ, strerror(errno));
562                 return;
563         }
564         cprintf("%d %s\n",LISTING_FOLLOWS,buf);
565
566         while (fgets(buf, (SIZ-1), mfp)!=NULL) {
567                 buf[strlen(buf)-1] = 0;
568                 do_help_subst(buf);
569                 cprintf("%s\n",buf);
570         }
571
572         fclose(mfp);
573         cprintf("000\n");
574 }
575
576
577 /*
578  * enter system messages or help
579  */
580 void cmd_emsg(char *mname)
581 {
582         FILE *mfp;
583         char targ[SIZ];
584         char buf[SIZ];
585         char *dirs[2];
586         int a;
587
588         unbuffer_output();
589
590         if (CtdlAccessCheck(ac_aide)) return;
591
592         extract(buf,mname,0);
593         for (a=0; a<strlen(buf); ++a) {         /* security measure */
594                 if (buf[a] == '/') buf[a] = '.';
595         }
596
597         dirs[0]=malloc(64);
598         dirs[1]=malloc(64);
599         strcpy(dirs[0],"messages");
600         strcpy(dirs[1],"help");
601         mesg_locate(targ,sizeof targ,buf,2,(const char**)dirs);
602         free(dirs[0]);
603         free(dirs[1]);
604
605         if (strlen(targ)==0) {
606                 snprintf(targ, sizeof targ, "./help/%s", buf);
607         }
608
609         mfp = fopen(targ,"w");
610         if (mfp==NULL) {
611                 cprintf("%d Cannot open '%s': %s\n",
612                         ERROR + INTERNAL_ERROR, targ, strerror(errno));
613                 return;
614         }
615         cprintf("%d %s\n", SEND_LISTING, targ);
616
617         while (client_getln(buf, sizeof buf), strcmp(buf, "000")) {
618                 fprintf(mfp, "%s\n", buf);
619         }
620
621         fclose(mfp);
622 }
623
624
625 /* Don't show the names of private rooms unless the viewing
626  * user also knows the rooms.
627  */
628 void GenerateRoomDisplay(char *real_room,
629                         struct CitContext *viewed,
630                         struct CitContext *viewer) {
631
632         int ra;
633
634         strcpy(real_room, viewed->room.QRname);
635         if (viewed->room.QRflags & QR_MAILBOX) {
636                 strcpy(real_room, &real_room[11]);
637         }
638         if (viewed->room.QRflags & QR_PRIVATE) {
639                 CtdlRoomAccess(&viewed->room, &viewer->user, &ra, NULL);
640                 if ( (ra & UA_KNOWN) == 0) {
641                         strcpy(real_room, "<private room>");
642                 }
643         }
644
645         if (viewed->cs_flags & CS_CHAT) {
646                 while (strlen(real_room) < 14)
647                         strcat(real_room, " ");
648
649                 strcpy(&real_room[14], "<chat>");
650         }
651
652 }
653
654 /*
655  * Convenience function.
656  */
657 int CtdlAccessCheck(int required_level) {
658
659         if (CC->internal_pgm) return(0);
660         if (required_level >= ac_internal) {
661                 cprintf("%d This is not a user-level command.\n",
662                         ERROR + HIGHER_ACCESS_REQUIRED);
663                 return(-1);
664         }
665
666         if ((required_level >= ac_logged_in) && (CC->logged_in == 0)) {
667                 cprintf("%d Not logged in.\n", ERROR + NOT_LOGGED_IN);
668                 return(-1);
669         }
670
671         if (CC->user.axlevel >= 6) return(0);
672         if (required_level >= ac_aide) {
673                 cprintf("%d This command requires Aide access.\n",
674                         ERROR + HIGHER_ACCESS_REQUIRED);
675                 return(-1);
676         }
677
678         if (is_room_aide()) return(0);
679         if (required_level >= ac_room_aide) {
680                 cprintf("%d This command requires Aide or Room Aide access.\n",
681                         ERROR + HIGHER_ACCESS_REQUIRED);
682                 return(-1);
683         }
684
685         /* shhh ... succeed quietly */
686         return(0);
687 }
688
689
690
691 /*
692  * Terminate another running session
693  */
694 void cmd_term(char *cmdbuf)
695 {
696         int session_num;
697         struct CitContext *ccptr;
698         int found_it = 0;
699         int allowed = 0;
700
701         session_num = extract_int(cmdbuf, 0);
702         if (session_num == CC->cs_pid) {
703                 cprintf("%d You can't kill your own session.\n", ERROR + ILLEGAL_VALUE);
704                 return;
705         }
706
707         lprintf(CTDL_DEBUG, "Locating session to kill\n");
708         begin_critical_section(S_SESSION_TABLE);
709         for (ccptr = ContextList; ccptr != NULL; ccptr = ccptr->next) {
710                 if (session_num == ccptr->cs_pid) {
711                         found_it = 1;
712                         if ((ccptr->user.usernum == CC->user.usernum)
713                            || (CC->user.axlevel >= 6)) {
714                                 allowed = 1;
715                                 ccptr->kill_me = 1;
716                         }
717                         else {
718                                 allowed = 0;
719                         }
720                 }
721         }
722         end_critical_section(S_SESSION_TABLE);
723
724         if (found_it) {
725                 if (allowed) {
726                         cprintf("%d Session terminated.\n", CIT_OK);
727                 }
728                 else {
729                         cprintf("%d You are not allowed to do that.\n",
730                                 ERROR + HIGHER_ACCESS_REQUIRED);
731                 }
732         }
733         else {
734                 cprintf("%d No such session.\n", ERROR + ILLEGAL_VALUE);
735         }
736 }
737
738
739
740
741
742 /* 
743  * get the paginator prompt
744  */
745 void cmd_more(void) {
746         cprintf("%d %s\n", CIT_OK, config.c_moreprompt);
747 }
748
749 /*
750  * echo 
751  */
752 void cmd_echo(char *etext)
753 {
754         cprintf("%d %s\n", CIT_OK, etext);
755 }
756
757
758
759 /* 
760  * identify as internal program
761  */
762 void cmd_ipgm(char *argbuf)
763 {
764         int secret;
765
766         secret = extract_int(argbuf, 0);
767
768         /* For security reasons, we do NOT allow this command to run
769          * over the network.  Local sockets only.
770          */
771         if (!CC->is_local_socket) {
772                 sleep(5);
773                 cprintf("%d Authentication failed.\n", ERROR + PASSWORD_REQUIRED);
774         }
775         else if (secret == config.c_ipgm_secret) {
776                 CC->internal_pgm = 1;
777                 strcpy(CC->curr_user, "<internal program>");
778                 CC->cs_flags = CC->cs_flags|CS_STEALTH;
779                 cprintf("%d Authenticated as an internal program.\n", CIT_OK);
780         }
781         else {
782                 sleep(5);
783                 cprintf("%d Authentication failed.\n", ERROR + PASSWORD_REQUIRED);
784                 lprintf(CTDL_ERR, "Warning: ipgm authentication failed.\n");
785                 CC->kill_me = 1;
786         }
787
788         /* Now change the ipgm secret for the next round. */
789         get_config();
790         config.c_ipgm_secret = rand();
791         put_config();
792 }
793
794
795 /*
796  * Shut down the server
797  */
798 void cmd_down(void) {
799
800         if (CtdlAccessCheck(ac_aide)) return;
801
802         cprintf("%d Shutting down server.  Goodbye.\n", CIT_OK);
803         time_to_die = 1;
804 }
805
806 /*
807  * Schedule or cancel a server shutdown
808  */
809 void cmd_scdn(char *argbuf)
810 {
811         int new_state;
812
813         if (CtdlAccessCheck(ac_aide)) return;
814
815         new_state = extract_int(argbuf, 0);
816         if ((new_state == 0) || (new_state == 1)) {
817                 ScheduledShutdown = new_state;
818         }
819         cprintf("%d %d\n", CIT_OK, ScheduledShutdown);
820 }
821
822
823 /*
824  * Set or unset asynchronous protocol mode
825  */
826 void cmd_asyn(char *argbuf)
827 {
828         int new_state;
829
830         new_state = extract_int(argbuf, 0);
831         if ((new_state == 0) || (new_state == 1)) {
832                 CC->is_async = new_state;
833         }
834         cprintf("%d %d\n", CIT_OK, CC->is_async);
835 }
836
837
838 /*
839  * Generate a "nonce" for APOP-style authentication.
840  *
841  * RFC 1725 et al specify a PID to be placed in front of the nonce.
842  * Quoth BTX: That would be stupid.
843  */
844 void generate_nonce(struct CitContext *con) {
845         struct timeval tv;
846
847         memset(con->cs_nonce, NONCE_SIZE, 0);
848         gettimeofday(&tv, NULL);
849         memset(con->cs_nonce, NONCE_SIZE, 0);
850         snprintf(con->cs_nonce, NONCE_SIZE, "<%d%ld@%s>",
851                 rand(), (long)tv.tv_usec, config.c_fqdn);
852 }
853
854
855
856
857 /*
858  * Back-end function for starting a session
859  */
860 void begin_session(struct CitContext *con)
861 {
862         int len;
863         struct sockaddr_in sin;
864
865         /* 
866          * Initialize some variables specific to our context.
867          */
868         con->logged_in = 0;
869         con->internal_pgm = 0;
870         con->download_fp = NULL;
871         con->upload_fp = NULL;
872         con->FirstExpressMessage = NULL;
873         time(&con->lastcmd);
874         time(&con->lastidle);
875         strcpy(con->lastcmdname, "    ");
876         strcpy(con->cs_clientname, "(unknown)");
877         strcpy(con->curr_user, NLI);
878         strcpy(con->net_node,"");
879         strcpy(con->fake_username, "");
880         strcpy(con->fake_postname, "");
881         strcpy(con->fake_hostname, "");
882         strcpy(con->fake_roomname, "");
883         generate_nonce(con);
884         safestrncpy(con->temp, tmpnam(NULL), sizeof con->temp);
885         safestrncpy(con->cs_host, config.c_fqdn, sizeof con->cs_host);
886         safestrncpy(con->cs_addr, "", sizeof con->cs_addr);
887         con->cs_host[sizeof con->cs_host - 1] = 0;
888         len = sizeof sin;
889         if (!CC->is_local_socket) {
890                 if (!getpeername(con->client_socket,
891                    (struct sockaddr *) &sin, &len))     /* should be socklen_t but doesn't work on Macintosh */
892                         locate_host(con->cs_host, sizeof con->cs_host,
893                                 con->cs_addr, sizeof con->cs_addr,
894                                 &sin.sin_addr);
895         }
896         else {
897                 strcpy(con->cs_host, "");
898         }
899         con->cs_flags = 0;
900         con->upload_type = UPL_FILE;
901         con->dl_is_net = 0;
902         con->FirstSessData = NULL;
903
904         con->nologin = 0;
905         if ((config.c_maxsessions > 0)&&(num_sessions > config.c_maxsessions))
906                 con->nologin = 1;
907
908         lprintf(CTDL_NOTICE, "Session started.\n");
909
910         /* Run any session startup routines registered by loadable modules */
911         PerformSessionHooks(EVT_START);
912 }
913
914
915 void citproto_begin_session() {
916         if (CC->nologin==1) {
917                 cprintf("%d %s: Too many users are already online "
918                         "(maximum is %d)\n",
919                         ERROR + MAX_SESSIONS_EXCEEDED,
920                         config.c_nodename, config.c_maxsessions);
921         }
922         else {
923                 cprintf("%d %s Citadel server ready.\n",
924                         CIT_OK, config.c_nodename);
925         }
926 }
927
928
929
930
931 /*
932  * This loop recognizes all server commands.
933  */
934 void do_command_loop(void) {
935         char cmdbuf[SIZ];
936
937         time(&CC->lastcmd);
938         memset(cmdbuf, 0, sizeof cmdbuf); /* Clear it, just in case */
939         if (client_getln(cmdbuf, sizeof cmdbuf) < 1) {
940                 lprintf(CTDL_ERR, "Client socket is broken; ending session\n");
941                 CC->kill_me = 1;
942                 return;
943         }
944
945         /* Log the server command, but don't show passwords... */
946         if ( (strncasecmp(cmdbuf, "PASS", 4))
947            && (strncasecmp(cmdbuf, "SETP", 4)) ) {
948                 lprintf(CTDL_INFO, "%s\n", cmdbuf);
949         }
950         else {
951                 lprintf(CTDL_INFO, "<password command sent>\n");
952         }
953
954         buffer_output();
955
956         /*
957          * Let other clients see the last command we executed, and
958          * update the idle time, but not NOOP, QNOP, PEXP, or GEXP.
959          */
960         if ( (strncasecmp(cmdbuf, "NOOP", 4))
961            && (strncasecmp(cmdbuf, "QNOP", 4))
962            && (strncasecmp(cmdbuf, "PEXP", 4))
963            && (strncasecmp(cmdbuf, "GEXP", 4)) ) {
964                 strcpy(CC->lastcmdname, "    ");
965                 safestrncpy(CC->lastcmdname, cmdbuf, 
966                         sizeof(CC->lastcmdname) );
967                 time(&CC->lastidle);
968         }
969                 
970         if ((strncasecmp(cmdbuf, "ENT0", 4))
971            && (strncasecmp(cmdbuf, "MESG", 4))
972            && (strncasecmp(cmdbuf, "MSGS", 4)))
973         {
974            CC->cs_flags &= ~CS_POSTING;
975         }
976                    
977         if (!strncasecmp(cmdbuf,"NOOP",4)) {
978                 cprintf("%d%cok\n", CIT_OK, CtdlCheckExpress() );
979         }
980         
981         else if (!strncasecmp(cmdbuf,"QNOP",4)) {
982                 /* do nothing, this command returns no response */
983         }
984
985         else if (!strncasecmp(cmdbuf,"QUIT",4)) {
986                 cprintf("%d Goodbye.\n", CIT_OK);
987                 CC->kill_me = 1;
988         }
989
990         else if (!strncasecmp(cmdbuf,"ASYN",4)) {
991                 cmd_asyn(&cmdbuf[5]);
992         }
993
994         else if (!strncasecmp(cmdbuf,"LOUT",4)) {
995                 if (CC->logged_in) logout(CC);
996                 cprintf("%d logged out.\n", CIT_OK);
997         }
998
999         else if (!strncasecmp(cmdbuf,"USER",4)) {
1000                 cmd_user(&cmdbuf[5]);
1001         }
1002
1003         else if (!strncasecmp(cmdbuf,"PASS",4)) {
1004                 cmd_pass(&cmdbuf[5]);
1005         }
1006
1007         else if (!strncasecmp(cmdbuf,"NEWU",4)) {
1008                 cmd_newu(&cmdbuf[5]);
1009         }
1010
1011         else if (!strncasecmp(cmdbuf,"CREU",4)) {
1012                 cmd_creu(&cmdbuf[5]);
1013         }
1014
1015         else if (!strncasecmp(cmdbuf,"SETP",4)) {
1016                 cmd_setp(&cmdbuf[5]);
1017         }
1018
1019         else if (!strncasecmp(cmdbuf,"LRMS",4)) {
1020                 cmd_lrms(&cmdbuf[5]);
1021         }
1022
1023         else if (!strncasecmp(cmdbuf,"LKRA",4)) {
1024                 cmd_lkra(&cmdbuf[5]);
1025         }
1026
1027         else if (!strncasecmp(cmdbuf,"LKRN",4)) {
1028                 cmd_lkrn(&cmdbuf[5]);
1029         }
1030
1031         else if (!strncasecmp(cmdbuf,"LKRO",4)) {
1032                 cmd_lkro(&cmdbuf[5]);
1033         }
1034
1035         else if (!strncasecmp(cmdbuf,"LZRM",4)) {
1036                 cmd_lzrm(&cmdbuf[5]);
1037         }
1038
1039         else if (!strncasecmp(cmdbuf,"LPRM",4)) {
1040                 cmd_lprm(&cmdbuf[5]);
1041         }
1042
1043         else if (!strncasecmp(cmdbuf,"GETU",4)) {
1044                 cmd_getu();
1045         }
1046
1047         else if (!strncasecmp(cmdbuf,"SETU",4)) {
1048                 cmd_setu(&cmdbuf[5]);
1049         }
1050
1051         else if (!strncasecmp(cmdbuf,"GOTO",4)) {
1052                 cmd_goto(&cmdbuf[5]);
1053         }
1054
1055         else if (!strncasecmp(cmdbuf,"MSGS",4)) {
1056                 cmd_msgs(&cmdbuf[5]);
1057         }
1058
1059         else if (!strncasecmp(cmdbuf,"WHOK",4)) {
1060                 cmd_whok();
1061         }
1062
1063         else if (!strncasecmp(cmdbuf,"RDIR",4)) {
1064                 cmd_rdir();
1065         }
1066
1067         else if (!strncasecmp(cmdbuf,"MSG0",4)) {
1068                 cmd_msg0(&cmdbuf[5]);
1069         }
1070
1071         else if (!strncasecmp(cmdbuf,"MSG2",4)) {
1072                 cmd_msg2(&cmdbuf[5]);
1073         }
1074
1075         else if (!strncasecmp(cmdbuf,"MSG3",4)) {
1076                 cmd_msg3(&cmdbuf[5]);
1077         }
1078
1079         else if (!strncasecmp(cmdbuf,"MSG4",4)) {
1080                 cmd_msg4(&cmdbuf[5]);
1081         }
1082
1083         else if (!strncasecmp(cmdbuf,"MSGP",4)) {
1084                 cmd_msgp(&cmdbuf[5]);
1085         }
1086
1087         else if (!strncasecmp(cmdbuf,"OPNA",4)) {
1088                 cmd_opna(&cmdbuf[5]);
1089         }
1090
1091         else if (!strncasecmp(cmdbuf,"INFO",4)) {
1092                 cmd_info();
1093         }
1094
1095         else if (!strncasecmp(cmdbuf,"SLRP",4)) {
1096                 cmd_slrp(&cmdbuf[5]);
1097         }
1098
1099         else if (!strncasecmp(cmdbuf,"INVT",4)) {
1100                 cmd_invt_kick(&cmdbuf[5],1);
1101         }
1102
1103         else if (!strncasecmp(cmdbuf,"KICK",4)) {
1104                 cmd_invt_kick(&cmdbuf[5],0);
1105         }
1106
1107         else if (!strncasecmp(cmdbuf,"GETR",4)) {
1108                 cmd_getr();
1109         }
1110
1111         else if (!strncasecmp(cmdbuf,"SETR",4)) {
1112                 cmd_setr(&cmdbuf[5]);
1113         }
1114
1115         else if (!strncasecmp(cmdbuf,"GETA",4)) {
1116                 cmd_geta();
1117         }
1118
1119         else if (!strncasecmp(cmdbuf,"SETA",4)) {
1120                 cmd_seta(&cmdbuf[5]);
1121         }
1122
1123         else if (!strncasecmp(cmdbuf,"ENT0",4)) {
1124                 cmd_ent0(&cmdbuf[5]);
1125         }
1126
1127         else if (!strncasecmp(cmdbuf,"RINF",4)) {
1128                 cmd_rinf();
1129         }
1130
1131         else if (!strncasecmp(cmdbuf,"DELE",4)) {
1132                 cmd_dele(&cmdbuf[5]);
1133         }
1134
1135         else if (!strncasecmp(cmdbuf,"KILL",4)) {
1136                 cmd_kill(&cmdbuf[5]);
1137         }
1138
1139         else if (!strncasecmp(cmdbuf,"CRE8",4)) {
1140                 cmd_cre8(&cmdbuf[5]);
1141         }
1142
1143         else if (!strncasecmp(cmdbuf,"MOVE",4)) {
1144                 cmd_move(&cmdbuf[5]);
1145         }
1146
1147         else if (!strncasecmp(cmdbuf,"FORG",4)) {
1148                 cmd_forg();
1149         }
1150
1151         else if (!strncasecmp(cmdbuf,"MESG",4)) {
1152                 cmd_mesg(&cmdbuf[5]);
1153         }
1154
1155         else if (!strncasecmp(cmdbuf,"EMSG",4)) {
1156                 cmd_emsg(&cmdbuf[5]);
1157         }
1158
1159         else if (!strncasecmp(cmdbuf,"GNUR",4)) {
1160                 cmd_gnur();
1161         }
1162
1163         else if (!strncasecmp(cmdbuf,"VALI",4)) {
1164                 cmd_vali(&cmdbuf[5]);
1165         }
1166
1167         else if (!strncasecmp(cmdbuf,"EINF",4)) {
1168                 cmd_einf(&cmdbuf[5]);
1169         }
1170
1171         else if (!strncasecmp(cmdbuf,"LIST",4)) {
1172                 cmd_list();
1173         }
1174
1175         else if (!strncasecmp(cmdbuf,"CHEK",4)) {
1176                 cmd_chek();
1177         }
1178
1179         else if (!strncasecmp(cmdbuf,"DELF",4)) {
1180                 cmd_delf(&cmdbuf[5]);
1181         }
1182
1183         else if (!strncasecmp(cmdbuf,"MOVF",4)) {
1184                 cmd_movf(&cmdbuf[5]);
1185         }
1186
1187         else if (!strncasecmp(cmdbuf,"NETF",4)) {
1188                 cmd_netf(&cmdbuf[5]);
1189         }
1190
1191         else if (!strncasecmp(cmdbuf,"OPEN",4)) {
1192                 cmd_open(&cmdbuf[5]);
1193         }
1194
1195         else if (!strncasecmp(cmdbuf,"CLOS",4)) {
1196                 cmd_clos();
1197         }
1198
1199         else if (!strncasecmp(cmdbuf,"UOPN",4)) {
1200                 cmd_uopn(&cmdbuf[5]);
1201         }
1202
1203         else if (!strncasecmp(cmdbuf,"UCLS",4)) {
1204                 cmd_ucls(&cmdbuf[5]);
1205         }
1206
1207         else if (!strncasecmp(cmdbuf,"READ",4)) {
1208                 cmd_read(&cmdbuf[5]);
1209         }
1210
1211         else if (!strncasecmp(cmdbuf,"WRIT",4)) {
1212                 cmd_writ(&cmdbuf[5]);
1213         }
1214
1215         else if (!strncasecmp(cmdbuf,"QUSR",4)) {
1216                 cmd_qusr(&cmdbuf[5]);
1217         }
1218
1219         else if (!strncasecmp(cmdbuf,"ECHO",4)) {
1220                 cmd_echo(&cmdbuf[5]);
1221         }
1222
1223         else if (!strncasecmp(cmdbuf,"OIMG",4)) {
1224                 cmd_oimg(&cmdbuf[5]);
1225         }
1226
1227         else if (!strncasecmp(cmdbuf,"MORE",4)) {
1228                 cmd_more();
1229         }
1230
1231         else if (!strncasecmp(cmdbuf,"NDOP",4)) {
1232                 cmd_ndop(&cmdbuf[5]);
1233         }
1234
1235         else if (!strncasecmp(cmdbuf,"NUOP",4)) {
1236                 cmd_nuop(&cmdbuf[5]);
1237         }
1238
1239         else if (!strncasecmp(cmdbuf,"LFLR",4)) {
1240                 cmd_lflr();
1241         }
1242
1243         else if (!strncasecmp(cmdbuf,"CFLR",4)) {
1244                 cmd_cflr(&cmdbuf[5]);
1245         }
1246
1247         else if (!strncasecmp(cmdbuf,"KFLR",4)) {
1248                 cmd_kflr(&cmdbuf[5]);
1249         }
1250
1251         else if (!strncasecmp(cmdbuf,"EFLR",4)) {
1252                 cmd_eflr(&cmdbuf[5]);
1253         }
1254
1255         else if (!strncasecmp(cmdbuf,"IDEN",4)) {
1256                 cmd_iden(&cmdbuf[5]);
1257         }
1258
1259         else if (!strncasecmp(cmdbuf,"IPGM",4)) {
1260                 cmd_ipgm(&cmdbuf[5]);
1261         }
1262
1263         else if (!strncasecmp(cmdbuf,"TERM",4)) {
1264                 cmd_term(&cmdbuf[5]);
1265         }
1266
1267         else if (!strncasecmp(cmdbuf,"DOWN",4)) {
1268                 cmd_down();
1269         }
1270
1271         else if (!strncasecmp(cmdbuf,"SCDN",4)) {
1272                 cmd_scdn(&cmdbuf[5]);
1273         }
1274
1275         else if (!strncasecmp(cmdbuf, "UIMG", 4)) {
1276                 cmd_uimg(&cmdbuf[5]);
1277         }
1278
1279         else if (!strncasecmp(cmdbuf, "TIME", 4)) {
1280                 cmd_time();
1281         }
1282
1283         else if (!strncasecmp(cmdbuf, "AGUP", 4)) {
1284                 cmd_agup(&cmdbuf[5]);
1285         }
1286
1287         else if (!strncasecmp(cmdbuf, "ASUP", 4)) {
1288                 cmd_asup(&cmdbuf[5]);
1289         }
1290
1291         else if (!strncasecmp(cmdbuf, "GPEX", 4)) {
1292                 cmd_gpex(&cmdbuf[5]);
1293         }
1294
1295         else if (!strncasecmp(cmdbuf, "SPEX", 4)) {
1296                 cmd_spex(&cmdbuf[5]);
1297         }
1298
1299         else if (!strncasecmp(cmdbuf, "CONF", 4)) {
1300                 cmd_conf(&cmdbuf[5]);
1301         }
1302
1303         else if (!strncasecmp(cmdbuf, "SEEN", 4)) {
1304                 cmd_seen(&cmdbuf[5]);
1305         }
1306
1307         else if (!strncasecmp(cmdbuf, "GTSN", 4)) {
1308                 cmd_gtsn(&cmdbuf[5]);
1309         }
1310
1311         else if (!strncasecmp(cmdbuf, "VIEW", 4)) {
1312                 cmd_view(&cmdbuf[5]);
1313         }
1314
1315         else if (!strncasecmp(cmdbuf, "ISME", 4)) {
1316                 cmd_isme(&cmdbuf[5]);
1317         }
1318
1319         else if (!DLoader_Exec_Cmd(cmdbuf)) {
1320                 cprintf("%d Unrecognized or unsupported command.\n",
1321                         ERROR + CMD_NOT_SUPPORTED);
1322                }
1323
1324         unbuffer_output();
1325
1326         /* Run any after-each-command routines registered by modules */
1327         PerformSessionHooks(EVT_CMD);
1328 }
1329
1330
1331 /*
1332  * This loop performs all asynchronous functions.
1333  */
1334 void do_async_loop(void) {
1335         PerformSessionHooks(EVT_ASYNC);
1336 }