Fix Crash; don't access pointers before checking them for NULL
[citadel.git] / webcit / webcit.c
1 /*
2  * This is the main transaction loop of the web service.  It maintains a
3  * persistent session to the Citadel server, handling HTTP WebCit requests as
4  * they arrive and presenting a user interface.
5  *
6  * Copyright (c) 1996-2011 by the citadel.org team
7  *
8  * This program is open source software.  You can redistribute it and/or
9  * modify it under the terms of the GNU General Public License as
10  * published by the Free Software Foundation; either version 3 of the
11  * License, or (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21  */
22
23 #define SHOW_ME_VAPPEND_PRINTF
24 #include <stdio.h>
25 #include <stdarg.h>
26 #include "webcit.h"
27 #include "groupdav.h"
28 #include "webserver.h"
29
30 StrBuf *csslocal = NULL;
31 HashList *HandlerHash = NULL;
32
33 void PutRequestLocalMem(void *Data, DeleteHashDataFunc DeleteIt)
34 {
35         wcsession *WCC = WC;
36         int n;
37         
38         n = GetCount(WCC->Hdr->HTTPHeaders);
39         Put(WCC->Hdr->HTTPHeaders, IKEY(n), Data, DeleteIt);
40 }
41
42 void DeleteWebcitHandler(void *vHandler)
43 {
44         WebcitHandler *Handler = (WebcitHandler*) vHandler;
45         FreeStrBuf(&Handler->Name);
46         FreeStrBuf(&Handler->DisplayName);
47         free (Handler);
48 }
49
50 void WebcitAddUrlHandler(const char * UrlString, long UrlSLen, 
51                          const char *DisplayName, long dslen,
52                          WebcitHandlerFunc F, 
53                          long Flags)
54 {
55         WebcitHandler *NewHandler;      
56         NewHandler = (WebcitHandler*) malloc(sizeof(WebcitHandler));
57         NewHandler->F = F;
58         NewHandler->Flags = Flags;
59         NewHandler->Name = NewStrBufPlain(UrlString, UrlSLen);
60         StrBufShrinkToFit(NewHandler->Name, 1);
61         NewHandler->DisplayName = NewStrBufPlain(DisplayName, dslen);
62         StrBufShrinkToFit(NewHandler->DisplayName, 1);
63         Put(HandlerHash, UrlString, UrlSLen, NewHandler, DeleteWebcitHandler);
64 }
65
66 void tmplput_HANDLER_DISPLAYNAME(StrBuf *Target, WCTemplputParams *TP) 
67 {
68         wcsession *WCC = WC;
69         if (WCC->Hdr->HR.Handler != NULL)
70                 StrBufAppendTemplate(Target, TP, WCC->Hdr->HR.Handler->DisplayName, 0);
71 }
72
73
74 /*
75  * web-printing funcion. uses our vsnprintf wrapper
76  */
77 #ifdef UBER_VERBOSE_DEBUGGING
78 void wcc_printf(const char *FILE, const char *FUNCTION, long LINE, const char *format,...)
79 #else
80 void wc_printf(const char *format,...)
81 #endif
82 {
83         wcsession *WCC = WC;
84         va_list arg_ptr;
85
86         if (WCC->WBuf == NULL)
87                 WCC->WBuf = NewStrBuf();
88 #ifdef UBER_VERBOSE_DEBUGGING
89         StrBufAppendPrintf(WCC->WBuf, "\n%s:%s:%d[", FILE, FUNCTION, LINE);
90 #endif
91
92         va_start(arg_ptr, format);
93         StrBufVAppendPrintf(WCC->WBuf, format, arg_ptr);
94         va_end(arg_ptr);
95 #ifdef UBER_VERBOSE_DEBUGGING
96         StrBufAppendPrintf(WCC->WBuf, "]\n");
97 #endif
98 }
99
100 /*
101  * http-header-printing funcion. uses our vsnprintf wrapper
102  */
103 void hprintf(const char *format,...)
104 {
105         wcsession *WCC = WC;
106         va_list arg_ptr;
107
108         va_start(arg_ptr, format);
109         StrBufVAppendPrintf(WCC->HBuf, format, arg_ptr);
110         va_end(arg_ptr);
111 }
112
113
114
115 /*
116  * wrap up an HTTP session, closes tags, etc.
117  *
118  * print_standard_html_footer should be set to:
119  * 0            - to transmit only,
120  * nonzero      - to append the closing tags
121  */
122 void wDumpContent(int print_standard_html_footer)
123 {
124         if (print_standard_html_footer) {
125                 wc_printf("</div> <!-- end of 'content' div -->\n");
126                 do_template("trailing", NULL);
127         }
128
129         /* If we've been saving it all up for one big output burst,
130          * go ahead and do that now.
131          */
132         end_burst();
133 }
134
135
136  
137
138 /*
139  * Output HTTP headers and leading HTML for a page
140  */
141 void output_headers(    int do_httpheaders,     /* 1 = output HTTP headers                        */
142                         int do_htmlhead,        /* 1 = output HTML <head> section and <body> opener */
143
144                         int do_room_banner,     /* 0=no, 1=yes,                              
145                                                  * 2 = I'm going to embed my own, so don't open the 
146                                                  *     <div id="content"> either.                  
147                                                  */
148
149                         int unset_cookies,      /* 1 = session is terminating, so unset the cookies */
150                         int suppress_check,     /* 1 = suppress check for instant messages        */
151                         int cache               /* 1 = allow browser to cache this page      */
152 ) {
153         wcsession *WCC = WC;
154         char httpnow[128];
155
156         hprintf("HTTP/1.1 200 OK\n");
157         http_datestring(httpnow, sizeof httpnow, time(NULL));
158
159         if (do_httpheaders) {
160                 if (WCC->serv_info != NULL)
161                         hprintf("Content-type: text/html; charset=utf-8\r\n"
162                                 "Server: %s / %s\n"
163                                 "Connection: close\r\n",
164                                 PACKAGE_STRING, 
165                                 ChrPtr(WCC->serv_info->serv_software));
166                 else
167                         hprintf("Content-type: text/html; charset=utf-8\r\n"
168                                 "Server: %s / [n/a]\n"
169                                 "Connection: close\r\n",
170                                 PACKAGE_STRING);
171         }
172
173         if (cache > 0) {
174                 char httpTomorow[128];
175
176                 http_datestring(httpTomorow, sizeof httpTomorow, 
177                                 time(NULL) + 60 * 60 * 24 * 2);
178
179                 hprintf("Pragma: public\r\n"
180                         "Cache-Control: max-age=3600, must-revalidate\r\n"
181                         "Last-modified: %s\r\n"
182                         "Expires: %s\r\n",
183                         httpnow,
184                         httpTomorow
185                 );
186         }
187         else {
188                 hprintf("Pragma: no-cache\r\n"
189                         "Cache-Control: no-store\r\n"
190                         "Expires: -1\r\n"
191                 );
192         }
193
194         if (cache < 2) stuff_to_cookie(unset_cookies);
195
196         if (do_htmlhead) {
197                 begin_burst();
198                 do_template("head", NULL);
199
200                 /* check for ImportantMessages (these display in a div overlaying the main screen) */
201                 if (!IsEmptyStr(WCC->ImportantMessage)) {
202                         wc_printf("<div id=\"important_message\">\n"
203                                 "<span class=\"imsg\">");
204                         StrEscAppend(WCC->WBuf, NULL, WCC->ImportantMessage, 0, 0);
205                         wc_printf("</span><br>\n"
206                                 "</div>\n"
207                         );
208                         StrBufAppendBufPlain(WCC->trailing_javascript,
209                                              HKEY("setTimeout('hide_imsg_popup()', 5000);       \n"), 
210                                              0
211                         );
212                         WCC->ImportantMessage[0] = 0;
213                 }
214                 else if (StrLength(WCC->ImportantMsg) > 0) {
215                         wc_printf("<div id=\"important_message\">\n"
216                                 "<span class=\"imsg\">");
217                         StrEscAppend(WCC->WBuf, WCC->ImportantMsg, NULL, 0, 0);
218                         wc_printf("</span><br>\n"
219                                 "</div>\n"
220                         );
221                         StrBufAppendBufPlain(WCC->trailing_javascript,
222                                              HKEY("setTimeout('hide_imsg_popup()', 5000);       \n"),
223                                              0
224                         );
225                         FlushStrBuf(WCC->ImportantMsg);
226                 }
227                 if ( (WCC->logged_in) && (!unset_cookies) ) {
228                         DoTemplate(HKEY("paging"), NULL, &NoCtx);
229                 }
230
231                 if (do_room_banner == 1) {
232                         tmplput_roombanner(NULL, NULL);
233                 }
234         }
235
236         if (do_room_banner == 1) {
237                 wc_printf("<div id=\"content\">\n");
238         }
239 }
240
241 void output_custom_content_header(const char *ctype) {
242   hprintf("HTTP/1.1 200 OK\r\n");
243   hprintf("Content-type: %s; charset=utf-8\r\n",ctype);
244   hprintf("Server: %s / %s\r\n", PACKAGE_STRING, ChrPtr(WC->serv_info->serv_software));
245   hprintf("Connection: close\r\n");
246 }
247
248
249 /*
250  * Generic function to do an HTTP redirect.  Easy and fun.
251  */
252 void http_redirect(const char *whichpage) {
253         hprintf("HTTP/1.1 302 Moved Temporarily\n");
254         hprintf("Location: %s\r\n", whichpage);
255         hprintf("URI: %s\r\n", whichpage);
256         hprintf("Content-type: text/html; charset=utf-8\r\n");
257         begin_burst();
258         wc_printf("<html><body>");
259         wc_printf("Go <a href=\"%s\">here</A>.", whichpage);
260         wc_printf("</body></html>\n");
261         end_burst();
262 }
263
264
265
266 /*
267  * Output a piece of content to the web browser using conformant HTTP and MIME semantics
268  */
269 void http_transmit_thing(const char *content_type, int is_static)
270 {
271
272         syslog(9, "http_transmit_thing(%s)%s\n", content_type, ((is_static > 0) ? " (static)" : ""));
273         output_headers(0, 0, 0, 0, 0, is_static);
274
275         hprintf("Content-type: %s\r\n"
276                 "Server: %s\r\n"
277                 "Connection: close\r\n",
278                 content_type,
279                 PACKAGE_STRING);
280
281         end_burst();
282 }
283
284
285 /*
286  * Convenience functions to display a page containing only a string
287  *
288  * titlebarcolor        color of the titlebar of the frame
289  * titlebarmsg          text to display in the title bar
290  * messagetext          body of the box
291  */
292 void convenience_page(const char *titlebarcolor, const char *titlebarmsg, const char *messagetext)
293 {
294         hprintf("HTTP/1.1 200 OK\n");
295         output_headers(1, 1, 2, 0, 0, 0);
296         wc_printf("<div id=\"banner\">\n");
297         wc_printf("<table width=100%% border=0 bgcolor=\"#%s\"><tr><td>", titlebarcolor);
298         wc_printf("<span class=\"titlebar\">%s</span>\n", titlebarmsg);
299         wc_printf("</td></tr></table>\n");
300         wc_printf("</div>\n<div id=\"content\">\n");
301         escputs(messagetext);
302
303         wc_printf("<hr />\n");
304         wDumpContent(1);
305 }
306
307
308 /*
309  * Display a blank page.
310  */
311 void blank_page(void) {
312         output_headers(1, 1, 0, 0, 0, 0);
313         wDumpContent(2);
314 }
315
316
317 /*
318  * A template has been requested
319  */
320 void url_do_template(void) {
321         const StrBuf *MimeType;
322         const StrBuf *Tmpl = sbstr("template");
323         begin_burst();
324         MimeType = DoTemplate(SKEY(Tmpl), NULL, &NoCtx);
325         http_transmit_thing(ChrPtr(MimeType), 0);
326 }
327
328
329
330 /*
331  * convenience function to indicate success
332  */
333 void display_success(char *successmessage)
334 {
335         convenience_page("007700", "OK", successmessage);
336 }
337
338
339 /*
340  * Authorization required page (sends a 401, causing the browser to request login credentials)
341  */
342 void authorization_required(void)
343 {
344         wcsession *WCC = WC;
345         const char *message = "";
346
347         hprintf("HTTP/1.1 401 Authorization Required\r\n");
348         hprintf(
349                 "Server: %s / %s\r\n"
350                 "Connection: close\r\n",
351                 PACKAGE_STRING, ChrPtr(WC->serv_info->serv_software)
352         );
353         hprintf("WWW-Authenticate: Basic realm=\"%s\"\r\n", ChrPtr(WC->serv_info->serv_humannode));
354         hprintf("Content-Type: text/html\r\n");
355         begin_burst();
356         wc_printf("<h1>");
357         wc_printf(_("Authorization Required"));
358         wc_printf("</h1>\r\n");
359         
360
361         if (WCC->ImportantMsg != NULL)
362                 message = ChrPtr(WCC->ImportantMsg);
363         else if (WCC->ImportantMessage != NULL)
364                 message = WCC->ImportantMessage;
365
366         wc_printf(_("The resource you requested requires a valid username and password. "
367                 "You could not be logged in: %s\n"), message);
368         wDumpContent(0);
369         end_webcit_session();
370 }
371
372 /*
373  * Convenience functions to wrap around asynchronous ajax responses
374  */
375 void begin_ajax_response(void) {
376         wcsession *WCC = WC;
377
378         FlushStrBuf(WCC->HBuf);
379         output_headers(0, 0, 0, 0, 0, 0);
380
381         hprintf("Content-type: text/html; charset=UTF-8\r\n"
382                 "Server: %s\r\n"
383                 "Connection: close\r\n"
384                 ,
385                 PACKAGE_STRING);
386         begin_burst();
387 }
388
389 /*
390  * print ajax response footer 
391  */
392 void end_ajax_response(void) {
393         wDumpContent(0);
394 }
395
396
397
398 /*
399  * Wraps a Citadel server command in an AJAX transaction.
400  */
401 void ajax_servcmd(void)
402 {
403         wcsession *WCC = WC;
404         int Done = 0;
405         StrBuf *Buf;
406         char *junk;
407         size_t len;
408
409         syslog(LOG_DEBUG, "ajax_servcmd() g_cmd=\"%s\"\n", bstr("g_cmd") );
410         begin_ajax_response();
411         Buf = NewStrBuf();
412         serv_puts(bstr("g_cmd"));
413         StrBuf_ServGetln(Buf);
414         StrBufAppendBuf(WCC->WBuf, Buf, 0);
415         StrBufAppendBufPlain(WCC->WBuf, HKEY("\n"), 0);
416         
417         switch (GetServerStatus(Buf, NULL)) {
418         case 8:
419                 serv_puts("\n\n000");
420                 if ( (StrLength(Buf)==3) && 
421                      !strcmp(ChrPtr(Buf), "000")) {
422                         StrBufAppendBufPlain(WCC->WBuf, HKEY("\000"), 0);
423                         break;
424                 }
425         case 1:
426                 while (!Done) {
427                         StrBuf_ServGetln(Buf);
428                         if ( (StrLength(Buf)==3) && 
429                              !strcmp(ChrPtr(Buf), "000")) {
430                                 Done = 1;
431                         }
432                         StrBufAppendBuf(WCC->WBuf, Buf, 0);
433                         StrBufAppendBufPlain(WCC->WBuf, HKEY("\n"), 0);
434                 }
435                 break;
436         case 4:
437                 text_to_server(bstr("g_input"));
438                 serv_puts("000");
439                 break;
440         case 6:
441                 len = atol(&ChrPtr(Buf)[4]);
442                 StrBuf_ServGetBLOBBuffered(Buf, len);
443                 break;
444         case 7:
445                 len = atol(&ChrPtr(Buf)[4]);
446                 junk = malloc(len);
447                 memset(junk, 0, len);
448                 serv_write(junk, len);
449                 free(junk);
450         }
451         
452         end_ajax_response();
453         
454         /*
455          * This is kind of an ugly hack, but this is the only place it can go.
456          * If the command was GEXP, then the instant messenger window must be
457          * running, so reset the "last_pager_check" watchdog timer so
458          * that page_popup() doesn't try to open it a second time.
459          */
460         if (!strncasecmp(bstr("g_cmd"), "GEXP", 4)) {
461                 WCC->last_pager_check = time(NULL);
462         }
463         FreeStrBuf(&Buf);
464 }
465
466
467 /*
468  * Helper function for the asynchronous check to see if we need
469  * to open the instant messenger window.
470  */
471 void seconds_since_last_gexp(void)
472 {
473         char buf[256];
474
475         if ( (time(NULL) - WC->last_pager_check) < 30) {
476                 wc_printf("NO\n");
477         }
478         else {
479                 memset(buf, 0, 5);
480                 serv_puts("NOOP");
481                 serv_getln(buf, sizeof buf);
482                 if (buf[3] == '*') {
483                         wc_printf("YES");
484                 }
485                 else {
486                         wc_printf("NO");
487                 }
488         }
489 }
490
491
492 /*
493  * Save a URL destination so we can go to it later
494  */
495 void push_destination(void) {
496         wcsession *WCC = WC;
497
498         if (!WCC) {
499                 wc_printf("no session");
500                 return;
501         }
502
503         FreeStrBuf(&WCC->PushedDestination);
504         WCC->PushedDestination = NewStrBufDup(SBSTR("url"));
505         syslog(9, "Push: %s\n", ChrPtr(WCC->PushedDestination));
506         wc_printf("OK");
507 }
508
509 /*
510  * Go to the URL saved by push_destination()
511  */
512 void pop_destination(void) {
513         wcsession *WCC = WC;
514
515         /*
516          * If we are in the middle of a new user signup, the server may request that
517          * we first pass through a registration screen.
518          */
519         if ((WCC) && (WCC->need_regi)) {
520                 if ((WCC->PushedDestination != NULL) && (StrLength(WCC->PushedDestination) > 0)) {
521                         /* Registering will take us to the My Citadel Config room, so save our place */
522                         StrBufAppendBufPlain(WCC->PushedDestination, HKEY("?go="), 0);
523                         StrBufUrlescAppend(WCC->PushedDestination, WCC->CurRoom.name, NULL);
524                 }
525                 WCC->need_regi = 0;
526                 display_reg(1);
527                 return;
528         }
529
530         /*
531          * Do something reasonable if we somehow ended up requesting a pop without
532          * having first done a push.
533          */
534         if ( (!WCC) || (WCC->PushedDestination == NULL) || (StrLength(WCC->PushedDestination) == 0) ) {
535                 do_welcome();
536                 return;
537         }
538
539         /*
540          * All righty then!  We have a destination saved, so go there now.
541          */
542         syslog(9, "Pop: %s\n", ChrPtr(WCC->PushedDestination));
543         http_redirect(ChrPtr(WCC->PushedDestination));
544 }
545
546
547
548 int ReadPostData(void)
549 {
550         int rc;
551         int urlencoded_post = 0;
552         wcsession *WCC = WC;
553         StrBuf *content = NULL;
554         
555         urlencoded_post = (strncasecmp(ChrPtr(WCC->Hdr->HR.ContentType), "application/x-www-form-urlencoded", 33) == 0) ;
556
557         content = NewStrBufPlain(NULL, WCC->Hdr->HR.ContentLength + 256);
558
559         if (!urlencoded_post)
560         {
561                 StrBufPrintf(content, 
562                      "Content-type: %s\n"
563                              "Content-length: %ld\n\n",
564                              ChrPtr(WCC->Hdr->HR.ContentType), 
565                              WCC->Hdr->HR.ContentLength);
566         }
567
568         /** Read the entire input data at once. */
569         rc = client_read_to(WCC->Hdr, content, 
570                             WCC->Hdr->HR.ContentLength,
571                             SLEEPING);
572         if (rc < 0)
573                 return rc;
574                 
575         
576         if (urlencoded_post) {
577                 ParseURLParams(content);
578         } else if (!strncasecmp(ChrPtr(WCC->Hdr->HR.ContentType), "multipart", 9)) {
579                 char *Buf;
580                 char *BufEnd;
581                 long len;
582
583                 len = StrLength(content);
584                 Buf = SmashStrBuf(&content);
585                 BufEnd = Buf + len;
586                 mime_parser(Buf, BufEnd, *upload_handler, NULL, NULL, NULL, 0);
587                 free(Buf);
588         } else if (WCC->Hdr->HR.ContentLength > 0) {
589                 WCC->upload = content;
590                 WCC->upload_length = StrLength(WCC->upload);
591                 content = NULL;
592         }
593         FreeStrBuf(&content);
594         return 1;
595 }
596
597
598 void ParseREST_URL(void)
599 {
600         StrBuf *Buf;
601         StrBuf *pFloor = NULL;
602         wcsession *WCC = WC;
603         long i = 0;
604         const char *pCh = NULL;
605         HashList *Floors;
606         void *vFloor;
607
608         syslog(1, "parsing rest URL: %s\n", ChrPtr(WCC->Hdr->HR.ReqLine));
609
610         WCC->Directory = NewHash(1, Flathash);
611         WCC->CurrentFloor = NULL;
612
613         Buf = NewStrBuf();
614         while (StrBufExtract_NextToken(Buf, WCC->Hdr->HR.ReqLine, &pCh,  '/') >= 0)
615         {
616                 if (StrLength(Buf) != 0) {
617                         /* ignore empty path segments */
618                         StrBufUnescape(Buf, 1);
619                         Put(WCC->Directory, IKEY(i), Buf, HFreeStrBuf);
620                         if (i==0)
621                                 pFloor = Buf;
622                         Buf = NewStrBuf();
623                 }
624                 i++;
625         }
626
627         FreeStrBuf(&Buf);
628         if (pFloor != NULL)
629         {
630                 Floors = GetFloorListHash(NULL, NULL);
631                 
632                 if (Floors != NULL)
633                 {
634                         if (GetHash(WCC->FloorsByName, SKEY(pFloor), &vFloor))
635                                 WCC->CurrentFloor = (Floor*) vFloor;
636                 }
637         }
638 }
639
640 int Conditional_REST_DEPTH(StrBuf *Target, WCTemplputParams *TP)
641 {
642         long Depth, IsDepth;
643         long offset = 0;
644         wcsession *WCC = WC;
645
646         if (WCC->Hdr->HR.Handler != NULL)
647                 offset ++;
648         Depth = GetTemplateTokenNumber(Target, TP, 2, 0);
649         IsDepth = GetCount(WCC->Directory) + offset;
650
651 //      LogTemplateError(Target, "bla", 1, TP, "REST_DEPTH: %ld : %ld\n", Depth, IsDepth);
652         if (Depth < 0) {
653                 Depth = -Depth;
654                 return IsDepth > Depth;
655         }
656         else 
657                 return Depth == IsDepth;
658 }
659
660
661
662 /*
663  * Entry point for WebCit transaction
664  */
665 void session_loop(void)
666 {
667         int Flags = 0;
668         int xhttp;
669         StrBuf *Buf;
670         
671         /*
672          * We stuff these with the values coming from the client cookies,
673          * so we can use them to reconnect a timed out session if we have to.
674          */
675         wcsession *WCC;
676       
677         WCC= WC;
678         WCC->upload_length = 0;
679         WCC->upload = NULL;
680         WCC->Hdr->nWildfireHeaders = 0;
681         if (WCC->Hdr->HR.Handler != NULL)
682                 Flags = WCC->Hdr->HR.Handler->Flags; /* so we can temporarily add our own... */
683
684         if (WCC->Hdr->HR.ContentLength > 0) {
685                 if (ReadPostData() < 0) {
686                         return;
687                 }
688         }
689
690         Buf = NewStrBuf();
691         WCC->trailing_javascript = NewStrBuf();
692
693         /* Convert base64-encoded URL's back to plain text */
694         if (!strncmp(ChrPtr(WCC->Hdr->this_page), "/B64", 4)) {
695                 StrBufCutLeft(WCC->Hdr->this_page, 4);
696                 StrBufDecodeBase64(WCC->Hdr->this_page);
697                 http_redirect(ChrPtr(WCC->Hdr->this_page));
698                 goto SKIP_ALL_THIS_CRAP;
699         }
700
701         /* If there are variables in the URL, we must grab them now */
702         if (WCC->Hdr->PlainArgs != NULL)
703                 ParseURLParams(WCC->Hdr->PlainArgs);
704
705         /* If the client sent a nonce that is incorrect, kill the request. */
706         if (havebstr("nonce")) {
707                 syslog(9, "Comparing supplied nonce %s to session nonce %d\n", 
708                         bstr("nonce"), WCC->nonce
709                 );
710                 if (ibstr("nonce") != WCC->nonce) {
711                         syslog(9, "Ignoring request with mismatched nonce.\n");
712                         hprintf("HTTP/1.1 404 Security check failed\r\n");
713                         hprintf("Content-Type: text/plain\r\n");
714                         begin_burst();
715                         wc_printf("Security check failed.\r\n");
716                         end_burst();
717                         goto SKIP_ALL_THIS_CRAP;
718                 }
719         }
720
721         /*
722          * If we're not connected to a Citadel server, try to hook up the connection now.
723          */
724         if (!WCC->connected) {
725                 if (GetConnected()) {
726                         hprintf("HTTP/1.1 503 Service Unavailable\r\n");
727                         hprintf("Content-Type: text/html\r\n");
728                         begin_burst();
729                         wc_printf("<html><head><title>503 Service Unavailable</title></head><body>\n");
730                         wc_printf(_("This program was unable to connect or stay "
731                                 "connected to the Citadel server.  Please report "
732                                 "this problem to your system administrator.")
733                         );
734                         wc_printf("<br>");
735                         wc_printf("<a href=\"http://www.citadel.org/doku.php/"
736                                 "faq:generalquestions:webcit_unable_to_connect\">%s</a>",
737                                 _("Read More...")
738                         );
739                         wc_printf("</body></html>\n");
740                         end_burst();
741                         goto SKIP_ALL_THIS_CRAP;
742                 }
743         }
744
745         /*
746          * If we're not logged in, but we have authentication data (either from
747          * a cookie or from http-auth), try logging in to Citadel using that.
748          */
749         if ((!WCC->logged_in)
750             && (StrLength(WCC->Hdr->c_username) > 0)
751             && (StrLength(WCC->Hdr->c_password) > 0))
752         {
753                 long Status;
754
755                 FlushStrBuf(Buf);
756                 serv_printf("USER %s", ChrPtr(WCC->Hdr->c_username));
757                 StrBuf_ServGetln(Buf);
758                 if (GetServerStatus(Buf, &Status) == 3) {
759                         serv_printf("PASS %s", ChrPtr(WCC->Hdr->c_password));
760                         StrBuf_ServGetln(Buf);
761                         if (GetServerStatus(Buf, NULL) == 2) {
762                                 become_logged_in(WCC->Hdr->c_username,
763                                                  WCC->Hdr->c_password, Buf);
764                         } else {
765                                 /* Should only display when password is wrong */
766                                 WCC->ImportantMsg = NewStrBufPlain(ChrPtr(Buf) + 4, StrLength(Buf) - 4);
767                                 authorization_required();
768                                 FreeStrBuf(&Buf);
769                                 goto SKIP_ALL_THIS_CRAP;
770                         }
771                 }
772                 else if (Status == 541) {
773                         WCC->logged_in = 1;
774                 }
775         }
776
777         xhttp = (WCC->Hdr->HR.eReqType != eGET) &&
778                 (WCC->Hdr->HR.eReqType != ePOST) &&
779                 (WCC->Hdr->HR.eReqType != eHEAD);
780
781         /*
782          * If a 'go' (or 'gotofirst') parameter has been specified, attempt to goto that room
783          * prior to doing anything else.
784          */
785         if (havebstr("go")) {
786                 int ret;
787                 syslog(9, "Explicit room selection: %s\n", bstr("go"));
788                 ret = gotoroom(sbstr("go"));    /* do quietly to avoid session output! */
789                 if ((ret/100) != 2) {
790                         syslog(1, "Unable to change to [%s]; Reason: %d\n", bstr("go"), ret);
791                 }
792         }
793         else if (havebstr("gotofirst")) {
794                 int ret;
795                 syslog(9, "Explicit room selection: %s\n", bstr("gotofirst"));
796                 ret = gotoroom(sbstr("gotofirst"));     /* do quietly to avoid session output! */
797                 if ((ret/100) != 2) {
798                         syslog(1, "Unable to change to [%s]; Reason: %d\n", bstr("gotofirst"), ret);
799                 }
800         }
801
802         /*
803          * If we aren't in any room yet, but we have cookie data telling us where we're
804          * supposed to be, and 'go' was not specified, then go there.
805          */
806         else if ( (StrLength(WCC->CurRoom.name) == 0) && ( (StrLength(WCC->Hdr->c_roomname) > 0) )) {
807                 int ret;
808
809                 syslog(9, "We are in '%s' but cookie indicates '%s', going there...\n",
810                         ChrPtr(WCC->CurRoom.name),
811                         ChrPtr(WCC->Hdr->c_roomname)
812                 );
813                 ret = gotoroom(WCC->Hdr->c_roomname);   /* do quietly to avoid session output! */
814                 if ((ret/100) != 2) {
815                         syslog(1, "COOKIEGOTO: Unable to change to [%s]; Reason: %d\n",
816                                 ChrPtr(WCC->Hdr->c_roomname), ret);
817                 }
818         }
819
820         if (WCC->Hdr->HR.Handler != NULL) {
821                 if (    (!WCC->logged_in)
822                         && ((WCC->Hdr->HR.Handler->Flags & ANONYMOUS) == 0)
823                         && (WCC->serv_info->serv_supports_guest == 0)
824                 ) {
825                         display_login();
826                 }
827                 else {
828 /*
829                         if ((WCC->Hdr->HR.Handler->Flags & PARSE_REST_URL) != 0)
830                                 ParseREST_URL();
831 */
832                         if ((WCC->Hdr->HR.Handler->Flags & AJAX) != 0)
833                                 begin_ajax_response();
834                         WCC->Hdr->HR.Handler->F();
835                         if ((WCC->Hdr->HR.Handler->Flags & AJAX) != 0)
836                                 end_ajax_response();
837                 }
838         }
839         /* When all else fails, display the default landing page or a main menu. */
840         else {
841                 /* 
842                  * ordinary browser users get a nice login screen, DAV etc. requsets
843                  * are given a 401 so they can handle it appropriate.
844                  */
845                 if (!WCC->logged_in)  {
846                         if (xhttp) {
847                                 authorization_required();
848                         }
849                         else {
850                                 display_default_landing_page();
851                         }
852                 }
853                 /*
854                  * Toplevel dav requests? or just a flat browser request? 
855                  */
856                 else {
857                         if (xhttp)
858                                 groupdav_main();
859                         else
860                                 display_main_menu();
861                 }
862         }
863
864 SKIP_ALL_THIS_CRAP:
865         FreeStrBuf(&Buf);
866         fflush(stdout);
867 }
868
869
870
871 /*
872  * Display the appropriate landing page for this site.
873  */
874 void display_default_landing_page(void) {
875         wcsession *WCC = WC;
876
877         if (WCC && WCC->serv_info && WCC->serv_info->serv_supports_guest) {
878                 /* default action.  probably revisit this. */
879                 StrBuf *teh_lobby = NewStrBufPlain(HKEY("_BASEROOM_"));
880                 smart_goto(teh_lobby);
881                 FreeStrBuf(&teh_lobby);
882         }
883         else {
884                 display_login();
885         }
886 }
887
888
889 /*
890  * Replacement for sleep() that uses select() in order to avoid SIGALRM
891  */
892 void sleeeeeeeeeep(int seconds)
893 {
894         struct timeval tv;
895
896         tv.tv_sec = seconds;
897         tv.tv_usec = 0;
898         select(0, NULL, NULL, NULL, &tv);
899 }
900
901 int Conditional_IS_HTTPS(StrBuf *Target, WCTemplputParams *TP)
902 {
903         return is_https != 0;
904 }
905
906 void AppendImportantMessage(const char *pch, long len)
907 {
908         wcsession *WCC = WC;
909
910         if (StrLength(WCC->ImportantMsg) > 0) {
911                 StrBufAppendBufPlain(WCC->ImportantMsg, HKEY("\n"), 0);
912         }
913                 
914         StrBufAppendBufPlain(WCC->ImportantMsg, pch, len, 0);
915 }
916
917 int ConditionalImportantMesage(StrBuf *Target, WCTemplputParams *TP)
918 {
919         wcsession *WCC = WC;
920         if (WCC != NULL)
921                 return ((!IsEmptyStr(WCC->ImportantMessage)) || 
922                         (StrLength(WCC->ImportantMsg) > 0));
923         else
924                 return 0;
925 }
926
927 void tmplput_importantmessage(StrBuf *Target, WCTemplputParams *TP)
928 {
929         wcsession *WCC = WC;
930         
931         if (WCC != NULL) {
932                 if (!IsEmptyStr(WCC->ImportantMessage)) {
933                         StrEscAppend(Target, NULL, WCC->ImportantMessage, 0, 0);
934                         WCC->ImportantMessage[0] = '\0';
935                 }
936                 else if (StrLength(WCC->ImportantMsg) > 0) {
937                         StrEscAppend(Target, WCC->ImportantMsg, NULL, 0, 0);
938                         FlushStrBuf(WCC->ImportantMsg);
939                 }
940         }
941 }
942
943 void tmplput_trailing_javascript(StrBuf *Target, WCTemplputParams *TP)
944 {
945         wcsession *WCC = WC;
946
947         if (WCC != NULL)
948                 StrBufAppendTemplate(Target, TP, WCC->trailing_javascript, 0);
949 }
950
951 void tmplput_csslocal(StrBuf *Target, WCTemplputParams *TP)
952 {
953         StrBufAppendBuf(Target, 
954                         csslocal, 0);
955 }
956
957 extern char static_local_dir[PATH_MAX];
958
959
960 void 
961 InitModule_WEBCIT
962 (void)
963 {
964         char dir[SIZ];
965         WebcitAddUrlHandler(HKEY("blank"), "", 0, blank_page, ANONYMOUS|COOKIEUNNEEDED|ISSTATIC);
966         WebcitAddUrlHandler(HKEY("do_template"), "", 0, url_do_template, ANONYMOUS);
967         WebcitAddUrlHandler(HKEY("sslg"), "", 0, seconds_since_last_gexp, AJAX|LOGCHATTY);
968         WebcitAddUrlHandler(HKEY("ajax_servcmd"), "", 0, ajax_servcmd, 0);
969         WebcitAddUrlHandler(HKEY("webcit"), "", 0, blank_page, URLNAMESPACE);
970         WebcitAddUrlHandler(HKEY("push"), "", 0, push_destination, AJAX);
971         WebcitAddUrlHandler(HKEY("pop"), "", 0, pop_destination, 0);
972
973         WebcitAddUrlHandler(HKEY("401"), "", 0, authorization_required, ANONYMOUS|COOKIEUNNEEDED);
974         RegisterConditional(HKEY("COND:IMPMSG"), 0, ConditionalImportantMesage, CTX_NONE);
975         RegisterConditional(HKEY("COND:REST:DEPTH"), 0, Conditional_REST_DEPTH, CTX_NONE);
976         RegisterConditional(HKEY("COND:IS_HTTPS"), 0, Conditional_IS_HTTPS, CTX_NONE);
977
978         RegisterNamespace("CSSLOCAL", 0, 0, tmplput_csslocal, NULL, CTX_NONE);
979         RegisterNamespace("IMPORTANTMESSAGE", 0, 0, tmplput_importantmessage, NULL, CTX_NONE);
980         RegisterNamespace("TRAILING_JAVASCRIPT", 0, 0, tmplput_trailing_javascript, NULL, CTX_NONE);
981         RegisterNamespace("URL:DISPLAYNAME", 0, 1, tmplput_HANDLER_DISPLAYNAME, NULL, CTX_NONE);
982
983         
984         snprintf(dir, SIZ, "%s/webcit.css", static_local_dir);
985         if (!access(dir, R_OK)) {
986                 syslog(9, "Using local Stylesheet [%s]\n", dir);
987                 csslocal = NewStrBufPlain(HKEY("<link href=\"static.local/webcit.css\" rel=\"stylesheet\" type=\"text/css\" />"));
988         }
989         else
990                 syslog(9, "No Site-local Stylesheet [%s] installed. \n", dir);
991
992 }
993
994 void
995 ServerStartModule_WEBCIT
996 (void)
997 {
998         HandlerHash = NewHash(1, NULL);
999 }
1000
1001
1002 void 
1003 ServerShutdownModule_WEBCIT
1004 (void)
1005 {
1006         FreeStrBuf(&csslocal);
1007         DeleteHash(&HandlerHash);
1008 }
1009
1010
1011
1012 void
1013 SessionNewModule_WEBCIT
1014 (wcsession *sess)
1015 {
1016         sess->ImportantMsg = NewStrBuf();
1017         sess->WBuf = NewStrBufPlain(NULL, SIZ * 4);
1018         sess->HBuf = NewStrBufPlain(NULL, SIZ / 4);
1019 }
1020
1021 void
1022 SessionDetachModule_WEBCIT
1023 (wcsession *sess)
1024 {
1025         DeleteHash(&sess->Directory);
1026
1027         FreeStrBuf(&sess->upload);
1028         sess->upload_length = 0;
1029         
1030         FreeStrBuf(&sess->trailing_javascript);
1031
1032         if (StrLength(sess->WBuf) > SIZ * 30) /* Bigger than 120K? release. */
1033         {
1034                 FreeStrBuf(&sess->WBuf);
1035                 sess->WBuf = NewStrBuf();
1036         }
1037         else
1038                 FlushStrBuf(sess->WBuf);
1039         FlushStrBuf(sess->HBuf);
1040 }
1041
1042 void 
1043 SessionDestroyModule_WEBCIT
1044 (wcsession *sess)
1045 {
1046         FreeStrBuf(&sess->WBuf);
1047         FreeStrBuf(&sess->HBuf);
1048         FreeStrBuf(&sess->ImportantMsg);
1049         FreeStrBuf(&sess->PushedDestination);
1050 }
1051