webcit/webcit.c

   1 // This is the main transaction loop of the web service.  It maintains a
   2 // persistent session to the Citadel server, handling HTTP WebCit requests as
   3 // they arrive and presenting a user interface.
   4 //
   5 // Copyright (c) 1996-2021 by the citadel.org team
   6 //
   7 // This program is open source software.  You can redistribute it and/or
   8 // modify it under the terms of the GNU General Public License, version 3.
   9
  10
  11 #define SHOW_ME_VAPPEND_PRINTF
  12 #include <stdio.h>
  13 #include <stdarg.h>
  14 #include "webcit.h"
  15 #include "dav.h"
  16 #include "webserver.h"
  17
  18 StrBuf *csslocal = NULL;
  19 HashList *HandlerHash = NULL;
  20
  21 void stuff_to_cookie(int unset_cookie);
  22 extern int GetConnected(void);
  23 extern int verbose;
  24
  25 void PutRequestLocalMem(void *Data, DeleteHashDataFunc DeleteIt)
  26 {
  27         int n;
  28
  29         n = GetCount(WC->Hdr->HTTPHeaders);
  30         Put(WC->Hdr->HTTPHeaders, IKEY(n), Data, DeleteIt);
  31 }
  32
  33 void DeleteWebcitHandler(void *vHandler)
  34 {
  35         WebcitHandler *Handler = (WebcitHandler*) vHandler;
  36         FreeStrBuf(&Handler->Name);
  37         FreeStrBuf(&Handler->DisplayName);
  38         free (Handler);
  39 }
  40
  41 void WebcitAddUrlHandler(const char * UrlString, long UrlSLen,
  42                          const char *DisplayName, long dslen,
  43                          WebcitHandlerFunc F,
  44                          long Flags)
  45 {
  46         WebcitHandler *NewHandler;
  47         NewHandler = (WebcitHandler*) malloc(sizeof(WebcitHandler));
  48         NewHandler->F = F;
  49         NewHandler->Flags = Flags;
  50         NewHandler->Name = NewStrBufPlain(UrlString, UrlSLen);
  51         StrBufShrinkToFit(NewHandler->Name, 1);
  52         NewHandler->DisplayName = NewStrBufPlain(DisplayName, dslen);
  53         StrBufShrinkToFit(NewHandler->DisplayName, 1);
  54         Put(HandlerHash, UrlString, UrlSLen, NewHandler, DeleteWebcitHandler);
  55 }
  56
  57 void tmplput_HANDLER_DISPLAYNAME(StrBuf *Target, WCTemplputParams *TP)
  58 {
  59         if (WC->Hdr->HR.Handler != NULL)
  60                 StrBufAppendTemplate(Target, TP, WC->Hdr->HR.Handler->DisplayName, 0);
  61 }
  62
  63
  64 /*
  65  * web-printing funcion. uses our vsnprintf wrapper
  66  */
  67 #ifdef UBER_VERBOSE_DEBUGGING
  68 void wcc_printf(const char *FILE, const char *FUNCTION, long LINE, const char *format,...)
  69 #else
  70 void wc_printf(const char *format,...)
  71 #endif
  72 {
  73         va_list arg_ptr;
  74
  75         if (WC->WBuf == NULL)
  76                 WC->WBuf = NewStrBuf();
  77 #ifdef UBER_VERBOSE_DEBUGGING
  78         StrBufAppendPrintf(WC->WBuf, "\n%s:%s:%d[", FILE, FUNCTION, LINE);
  79 #endif
  80
  81         va_start(arg_ptr, format);
  82         StrBufVAppendPrintf(WC->WBuf, format, arg_ptr);
  83         va_end(arg_ptr);
  84 #ifdef UBER_VERBOSE_DEBUGGING
  85         StrBufAppendPrintf(WC->WBuf, "]\n");
  86 #endif
  87 }
  88
  89 /*
  90  * http-header-printing funcion. uses our vsnprintf wrapper
  91  */
  92 void hprintf(const char *format,...)
  93 {
  94         va_list arg_ptr;
  95
  96         va_start(arg_ptr, format);
  97         StrBufVAppendPrintf(WC->HBuf, format, arg_ptr);
  98         va_end(arg_ptr);
  99 }
 100
 101
 102
 103 /*
 104  * wrap up an HTTP session, closes tags, etc.
 105  *
 106  * print_standard_html_footer should be set to:
 107  * 0            - to transmit only,
 108  * nonzero      - to append the closing tags
 109  */
 110 void wDumpContent(int print_standard_html_footer)
 111 {
 112         if (print_standard_html_footer) {
 113                 wc_printf("</div> <!-- end of 'content' div -->\n");
 114                 do_template("trailing");
 115         }
 116
 117         /* If we've been saving it all up for one big output burst,
 118          * go ahead and do that now.
 119          */
 120         end_burst();
 121 }
 122
 123
 124
 125
 126 /*
 127  * Output HTTP headers and leading HTML for a page
 128  */
 129 void output_headers(    int do_httpheaders,     /* 1 = output HTTP headers                        */
 130                         int do_htmlhead,        /* 1 = output HTML <head> section and <body> opener */
 131                         int do_room_banner,     /* 1 = include the room banner and <div id="content"></div> */
 132                         int unset_cookies,      /* 1 = session is terminating, so unset the cookies */
 133                         int suppress_check,     /* 1 = suppress check for instant messages        */
 134                         int cache               /* 1 = allow browser to cache this page      */
 135 ) {
 136         char httpnow[128];
 137
 138         if (WC->isFailure)
 139                 hprintf("HTTP/2.2 500 Internal Server Error");
 140         else if (WC->Hdr->HaveRange > 1)
 141                 hprintf("HTTP/1.1 206 Partial Content\r\n");
 142         else
 143                 hprintf("HTTP/1.1 200 OK\r\n");
 144
 145         http_datestring(httpnow, sizeof httpnow, time(NULL));
 146
 147         if (do_httpheaders) {
 148                 if (WC->serv_info != NULL)
 149                         hprintf("Content-type: text/html; charset=utf-8\r\n"
 150                                 "Server: %s / %s\n"
 151                                 "Connection: close\r\n",
 152                                 PACKAGE_STRING,
 153                                 ChrPtr(WC->serv_info->serv_software));
 154                 else
 155                         hprintf("Content-type: text/html; charset=utf-8\r\n"
 156                                 "Server: %s / [n/a]\n"
 157                                 "Connection: close\r\n",
 158                                 PACKAGE_STRING);
 159         }
 160
 161         if (cache > 0) {
 162                 char httpTomorow[128];
 163
 164                 http_datestring(httpTomorow, sizeof httpTomorow,
 165                                 time(NULL) + 60 * 60 * 24 * 2);
 166
 167                 hprintf("Pragma: public\r\n"
 168                         "Cache-Control: max-age=3600, must-revalidate\r\n"
 169                         "Last-modified: %s\r\n"
 170                         "Expires: %s\r\n",
 171                         httpnow,
 172                         httpTomorow
 173                 );
 174         }
 175         else {
 176                 hprintf("Pragma: no-cache\r\n"
 177                         "Cache-Control: no-store\r\n"
 178                         "Expires: -1\r\n"
 179                 );
 180         }
 181
 182         if (cache < 2) stuff_to_cookie(unset_cookies);
 183
 184         if (do_htmlhead) {
 185                 begin_burst();
 186                 do_template("head");
 187                 if ( (WC->logged_in) && (!unset_cookies) ) {
 188                         DoTemplate(HKEY("paging"), NULL, &NoCtx);
 189                 }
 190                 if (do_room_banner) {
 191                         tmplput_roombanner(NULL, NULL);
 192                 }
 193         }
 194
 195         if (do_room_banner) {
 196                 wc_printf("<div id=\"content\">\n");
 197         }
 198 }
 199
 200 void output_custom_content_header(const char *ctype) {
 201         hprintf("HTTP/1.1 200 OK\r\n");
 202         hprintf("Content-type: %s; charset=utf-8\r\n",ctype);
 203         hprintf("Server: %s / %s\r\n", PACKAGE_STRING, ChrPtr(WC->serv_info->serv_software));
 204         hprintf("Connection: close\r\n");
 205 }
 206
 207
 208 /*
 209  * Generic function to do an HTTP redirect.  Easy and fun.
 210  */
 211 void http_redirect(const char *whichpage) {
 212         hprintf("HTTP/1.1 302 Moved Temporarily\n");
 213         hprintf("Location: %s\r\n", whichpage);
 214         hprintf("URI: %s\r\n", whichpage);
 215         hprintf("Content-type: text/html; charset=utf-8\r\n");
 216         stuff_to_cookie(0);
 217         begin_burst();
 218         wc_printf("<html><body>");
 219         wc_printf("Go <a href=\"%s\">here</A>.", whichpage);
 220         wc_printf("</body></html>\n");
 221         end_burst();
 222 }
 223
 224
 225
 226 /*
 227  * Output a piece of content to the web browser using conformant HTTP and MIME semantics.
 228  *
 229  * If this function is called, it is expected that begin_burst() has already been called
 230  * and some sort of content has been fed into the buffer.  This function will transmit a
 231  * bunch of headers to the client.  end_burst() will add some headers of its own, and then
 232  * transmit the buffered content to the client.
 233  */
 234 void http_transmit_thing(const char *content_type, int is_static)
 235 {
 236         if (verbose)
 237                 syslog(LOG_DEBUG, "http_transmit_thing(%s)%s", content_type, ((is_static > 0) ? " (static)" : ""));
 238         output_headers(0, 0, 0, 0, 0, is_static);
 239
 240         hprintf("Content-type: %s\r\n"
 241                 "Server: %s\r\n"
 242                 "Connection: close\r\n",
 243                 content_type,
 244                 PACKAGE_STRING);
 245
 246         end_burst();
 247 }
 248
 249 void http_transmit_headers(const char *content_type, int is_static, long is_chunked, int is_gzip)
 250 {
 251         if (verbose)
 252                 syslog(LOG_DEBUG, "http_transmit_thing(%s)%s", content_type, ((is_static > 0) ? " (static)" : ""));
 253         output_headers(0, 0, 0, 0, 0, is_static);
 254
 255         if (is_gzip)
 256                 hprintf("Content-encoding: gzip\r\n");
 257
 258         if (WC->Hdr->HaveRange)
 259                 hprintf("Accept-Ranges: bytes\r\n"
 260                         "Content-Range: bytes %ld-%ld/%ld\r\n",
 261                         WC->Hdr->RangeStart,
 262                         WC->Hdr->RangeTil,
 263                         WC->Hdr->TotalBytes);
 264
 265         hprintf("Content-type: %s\r\n"
 266                 "Server: "PACKAGE_STRING"\r\n"
 267                 "%s"
 268                 "Connection: close\r\n\r\n",
 269                 content_type,
 270                 (is_chunked)?"Transfer-Encoding: chunked\r\n":"");
 271 }
 272
 273
 274 /*
 275  * Convenience functions to display a page containing only a string
 276  *
 277  * titlebarcolor        color of the titlebar of the frame
 278  * titlebarmsg          text to display in the title bar
 279  * messagetext          body of the box
 280  */
 281 void convenience_page(const char *titlebarcolor, const char *titlebarmsg, const char *messagetext)
 282 {
 283         hprintf("HTTP/1.1 200 OK\n");
 284         output_headers(1, 1, 1, 0, 0, 0);
 285         wc_printf("<div id=\"room_banner_override\">\n");
 286         wc_printf("<table width=100%% border=0 bgcolor=\"#%s\"><tr><td>", titlebarcolor);
 287         wc_printf("<span class=\"titlebar\">%s</span>\n", titlebarmsg);
 288         wc_printf("</td></tr></table>\n");
 289         wc_printf("</div>\n<div id=\"content\">\n");
 290         escputs(messagetext);
 291         wc_printf("<hr />\n");
 292         wDumpContent(1);
 293 }
 294
 295
 296 /*
 297  * Display a blank page.
 298  */
 299 void blank_page(void) {
 300         output_headers(1, 1, 0, 0, 0, 0);
 301         wDumpContent(2);
 302 }
 303
 304
 305 /*
 306  * A template has been requested
 307  */
 308 void url_do_template(void) {
 309         const StrBuf *MimeType;
 310         const StrBuf *Tmpl = sbstr("template");
 311         begin_burst();
 312         MimeType = DoTemplate(SKEY(Tmpl), NULL, &NoCtx);
 313         http_transmit_thing(ChrPtr(MimeType), 0);
 314 }
 315
 316
 317
 318 /*
 319  * convenience function to indicate success
 320  */
 321 void display_success(const char *successmessage)
 322 {
 323         convenience_page("007700", "OK", successmessage);
 324 }
 325
 326
 327 /*
 328  * Authorization required page (sends a 401, causing the browser to request login credentials)
 329  */
 330 void authorization_required(void)
 331 {
 332         const char *message = "";
 333
 334         hprintf("HTTP/1.1 401 Authorization Required\r\n");
 335         hprintf(
 336                 "Server: %s / %s\r\n"
 337                 "Connection: close\r\n",
 338                 PACKAGE_STRING, ChrPtr(WC->serv_info->serv_software)
 339         );
 340         hprintf("WWW-Authenticate: Basic realm=\"%s\"\r\n", ChrPtr(WC->serv_info->serv_humannode));
 341
 342         /* if this is a false cookie authentication, remove it to avoid endless loops. */
 343         if (StrLength(WC->Hdr->HR.RawCookie) > 0)
 344                 stuff_to_cookie(1);
 345
 346         hprintf("Content-Type: text/html\r\n");
 347         begin_burst();
 348         wc_printf("<h1>");
 349         wc_printf(_("Authorization Required"));
 350         wc_printf("</h1>\r\n");
 351
 352         if (WC->ImportantMsg != NULL) {
 353                 message = ChrPtr(WC->ImportantMsg);
 354         }
 355
 356         wc_printf(
 357                 _("The resource you requested requires a valid username and password. "
 358                 "You could not be logged in: %s\n"),
 359                 message
 360         );
 361         wDumpContent(0);
 362 }
 363
 364
 365 /*
 366  * Convenience functions to wrap around asynchronous ajax responses
 367  */
 368 void begin_ajax_response(void) {
 369
 370         FlushStrBuf(WC->HBuf);
 371         output_headers(0, 0, 0, 0, 0, 0);
 372
 373         hprintf("Content-type: text/html; charset=UTF-8\r\n"
 374                 "Server: %s\r\n"
 375                 "Connection: close\r\n"
 376                 ,
 377                 PACKAGE_STRING);
 378         begin_burst();
 379 }
 380
 381
 382 /*
 383  * print ajax response footer
 384  */
 385 void end_ajax_response(void) {
 386         wDumpContent(0);
 387 }
 388
 389
 390 /*
 391  * Wraps a Citadel server command in an AJAX transaction.
 392  */
 393 void ajax_servcmd(void) {
 394         int Done = 0;
 395         StrBuf *Buf;
 396         char *junk;
 397         size_t len;
 398
 399         if (verbose) {
 400                 syslog(LOG_DEBUG, "ajax_servcmd() g_cmd=\"%s\"", bstr("g_cmd") );
 401         }
 402         begin_ajax_response();
 403         Buf = NewStrBuf();
 404         serv_puts(bstr("g_cmd"));
 405         StrBuf_ServGetln(Buf);
 406         StrBufAppendBuf(WC->WBuf, Buf, 0);
 407         StrBufAppendBufPlain(WC->WBuf, HKEY("\n"), 0);
 408
 409         switch (GetServerStatus(Buf, NULL)) {
 410         case 8:
 411                 serv_puts("\n\n000");
 412                 if ( (StrLength(Buf)==3) &&
 413                      !strcmp(ChrPtr(Buf), "000")) {
 414                         StrBufAppendBufPlain(WC->WBuf, HKEY("\000"), 0);
 415                         break;
 416                 }
 417         case 1:
 418                 while (!Done) {
 419                         if (StrBuf_ServGetln(Buf) < 0)
 420                                 break;
 421                         if ( (StrLength(Buf)==3) &&
 422                              !strcmp(ChrPtr(Buf), "000")) {
 423                                 Done = 1;
 424                         }
 425                         StrBufAppendBuf(WC->WBuf, Buf, 0);
 426                         StrBufAppendBufPlain(WC->WBuf, HKEY("\n"), 0);
 427                 }
 428                 break;
 429         case 4:
 430                 text_to_server(bstr("g_input"));
 431                 serv_puts("000");
 432                 break;
 433         case 6:
 434                 len = atol(&ChrPtr(Buf)[4]);
 435                 StrBuf_ServGetBLOBBuffered(Buf, len);
 436                 break;
 437         case 7:
 438                 len = atol(&ChrPtr(Buf)[4]);
 439                 junk = malloc(len);
 440                 memset(junk, 0, len);
 441                 serv_write(junk, len);
 442                 free(junk);
 443         }
 444
 445         end_ajax_response();
 446
 447         /*
 448          * This is kind of an ugly hack, but this is the only place it can go.
 449          * If the command was GEXP, then the instant messenger window must be
 450          * running, so reset the "last_pager_check" watchdog timer so
 451          * that page_popup() doesn't try to open it a second time. TODO: page_popup isn't with us anymore.
 452          */
 453         if (!strncasecmp(bstr("g_cmd"), "GEXP", 4)) {
 454                 WC->last_pager_check = time(NULL);
 455         }
 456         FreeStrBuf(&Buf);
 457 }
 458
 459
 460 /*
 461  * Helper function for the asynchronous check to see if we need
 462  * to open the instant messenger window.
 463  */
 464 void seconds_since_last_gexp(void)
 465 {
 466         char buf[256];
 467
 468         if ( (time(NULL) - WC->last_pager_check) < 30) {
 469                 wc_printf("NO\n");
 470         }
 471         else {
 472                 memset(buf, 0, 5);
 473                 serv_puts("NOOP");
 474                 serv_getln(buf, sizeof buf);
 475                 if (buf[3] == '*') {
 476                         wc_printf("YES");
 477                 }
 478                 else {
 479                         wc_printf("NO");
 480                 }
 481         }
 482 }
 483
 484
 485 /*
 486  * Save a URL destination so we can go to it later
 487  */
 488 void push_destination(void) {
 489
 490         if (!WC) {
 491                 wc_printf("no session");
 492                 return;
 493         }
 494
 495         FreeStrBuf(&WC->PushedDestination);
 496         WC->PushedDestination = NewStrBufDup(sbstr("url"));
 497         if (verbose)
 498                 syslog(LOG_DEBUG, "Push: %s", ChrPtr(WC->PushedDestination));
 499         wc_printf("OK");
 500 }
 501
 502
 503 /*
 504  * Go to the URL saved by push_destination()
 505  */
 506 void pop_destination(void) {
 507         /*
 508          * If we are in the middle of a new user signup, the server may request that
 509          * we first pass through a registration screen.
 510          */
 511         if ((WC) && (WC->need_regi)) {
 512                 if ((WC->PushedDestination != NULL) && (StrLength(WC->PushedDestination) > 0)) {
 513                         /* Registering will take us to the My Citadel Config room, so save our place */
 514                         StrBufAppendBufPlain(WC->PushedDestination, HKEY("?go="), 0);
 515                         StrBufUrlescAppend(WC->PushedDestination, WC->CurRoom.name, NULL);
 516                 }
 517                 WC->need_regi = 0;
 518                 display_reg(1);
 519                 return;
 520         }
 521
 522         /*
 523          * Do something reasonable if we somehow ended up requesting a pop without
 524          * having first done a push.
 525          */
 526         if ( (!WC) || (WC->PushedDestination == NULL) || (StrLength(WC->PushedDestination) == 0) ) {
 527                 do_welcome();
 528                 return;
 529         }
 530
 531         /*
 532          * All righty then!  We have a destination saved, so go there now.
 533          */
 534         if (verbose) {
 535                 syslog(LOG_DEBUG, "Pop: %s", ChrPtr(WC->PushedDestination));
 536         }
 537         http_redirect(ChrPtr(WC->PushedDestination));
 538 }
 539
 540
 541 int ReadPostData(void) {
 542         int rc;
 543         int urlencoded_post = 0;
 544         StrBuf *content = NULL;
 545
 546         urlencoded_post = (strncasecmp(ChrPtr(WC->Hdr->HR.ContentType), "application/x-www-form-urlencoded", 33) == 0) ;
 547
 548         content = NewStrBufPlain(NULL, WC->Hdr->HR.ContentLength + 256);
 549
 550         if (!urlencoded_post) {
 551                 StrBufPrintf(content,
 552                         "Content-type: %s\n"
 553                         "Content-length: %ld\n\n",
 554                         ChrPtr(WC->Hdr->HR.ContentType),
 555                         WC->Hdr->HR.ContentLength
 556                 );
 557         }
 558
 559         /* Read the entire input data at once. */
 560         rc = client_read_to(WC->Hdr, content, WC->Hdr->HR.ContentLength, SLEEPING);
 561         if (rc < 0) {
 562                 return rc;
 563         }
 564
 565         if (urlencoded_post) {
 566                 ParseURLParams(content);
 567         }
 568         else if (!strncasecmp(ChrPtr(WC->Hdr->HR.ContentType), "multipart", 9)) {
 569                 char *Buf;
 570                 char *BufEnd;
 571                 long len;
 572
 573                 len = StrLength(content);
 574                 Buf = SmashStrBuf(&content);
 575                 BufEnd = Buf + len;
 576                 mime_parser(Buf, BufEnd, *upload_handler, NULL, NULL, NULL, 0);
 577                 free(Buf);
 578         }
 579         else if (WC->Hdr->HR.ContentLength > 0) {
 580                 WC->upload = content;
 581                 WC->upload_length = StrLength(WC->upload);
 582                 content = NULL;
 583         }
 584         FreeStrBuf(&content);
 585         return 1;
 586 }
 587
 588
 589 int Conditional_REST_DEPTH(StrBuf *Target, WCTemplputParams *TP)
 590 {
 591         long Depth, IsDepth;
 592         long offset = 0;
 593
 594         if (WC->Hdr->HR.Handler != NULL)
 595                 offset ++;
 596         Depth = GetTemplateTokenNumber(Target, TP, 2, 0);
 597         IsDepth = GetCount(WC->Directory) + offset;
 598
 599 //      LogTemplateError(Target, "bla", 1, TP, "REST_DEPTH: %ld : %ld\n", Depth, IsDepth);
 600         if (Depth < 0) {
 601                 Depth = -Depth;
 602                 return IsDepth > Depth;
 603         }
 604         else
 605                 return Depth == IsDepth;
 606 }
 607
 608
 609
 610 /*
 611  * Entry point for WebCit transaction
 612  */
 613 void session_loop(void)
 614 {
 615         int xhttp;
 616         StrBuf *Buf;
 617
 618         /*
 619          * We stuff these with the values coming from the client cookies,
 620          * so we can use them to reconnect a timed out session if we have to.
 621          */
 622         WC->upload_length = 0;
 623         WC->upload = NULL;
 624         WC->Hdr->nWildfireHeaders = 0;
 625
 626         if (WC->Hdr->HR.ContentLength > 0) {
 627                 if (ReadPostData() < 0) {
 628                         return;
 629                 }
 630         }
 631
 632         Buf = NewStrBuf();
 633         WC->trailing_javascript = NewStrBuf();
 634
 635         /* Convert base64-encoded URL's back to plain text */
 636         if (!strncmp(ChrPtr(WC->Hdr->this_page), "/B64", 4)) {
 637                 StrBufCutLeft(WC->Hdr->this_page, 4);
 638                 StrBufDecodeBase64(WC->Hdr->this_page);
 639                 http_redirect(ChrPtr(WC->Hdr->this_page));
 640                 goto SKIP_ALL_THIS_CRAP;
 641         }
 642
 643         /* If there are variables in the URL, we must grab them now */
 644         if (WC->Hdr->PlainArgs != NULL) {
 645                 ParseURLParams(WC->Hdr->PlainArgs);
 646         }
 647
 648         /* If the client sent a nonce that is incorrect, kill the request. */
 649         if (havebstr("nonce")) {
 650                 if (verbose) {
 651                         syslog(LOG_DEBUG, "Comparing supplied nonce %s to session nonce %d", bstr("nonce"), WC->nonce);
 652                 }
 653                 if (ibstr("nonce") != WC->nonce) {
 654                         syslog(LOG_INFO, "Ignoring request with mismatched nonce.");
 655                         hprintf("HTTP/1.1 404 Security check failed\r\n");
 656                         hprintf("Content-Type: text/plain\r\n");
 657                         begin_burst();
 658                         wc_printf("Security check failed.\r\n");
 659                         end_burst();
 660                         goto SKIP_ALL_THIS_CRAP;
 661                 }
 662         }
 663
 664         /*
 665          * If we're not connected to a Citadel server, try to hook up the connection now.
 666          */
 667         if (!WC->connected) {
 668                 if (GetConnected()) {
 669                         hprintf("HTTP/1.1 503 Service Unavailable\r\n");
 670                         hprintf("Content-Type: text/html\r\n");
 671                         begin_burst();
 672                         wc_printf("<html><head><title>503 Service Unavailable</title></head><body>\n");
 673                         wc_printf(_("This program was unable to connect or stay "
 674                                 "connected to the Citadel server.  Please report "
 675                                 "this problem to your system administrator.")
 676                         );
 677                         wc_printf("<br>");
 678                         wc_printf("<a href=\"http://www.citadel.org/doku.php/"
 679                                 "faq:generalquestions:webcit_unable_to_connect\">%s</a>",
 680                                 _("Read More...")
 681                         );
 682                         wc_printf("</body></html>\n");
 683                         end_burst();
 684                         goto SKIP_ALL_THIS_CRAP;
 685                 }
 686         }
 687
 688         /*
 689          * If we're not logged in, but we have authentication data (either from
 690          * a cookie or from http-auth), try logging in to Citadel using that.
 691          */
 692         if (    (!WC->logged_in)
 693                 && (StrLength(WC->Hdr->c_username) > 0)
 694                 && (StrLength(WC->Hdr->c_password) > 0)
 695         ) {
 696                 long Status;
 697
 698                 FlushStrBuf(Buf);
 699                 serv_printf("USER %s", ChrPtr(WC->Hdr->c_username));
 700                 StrBuf_ServGetln(Buf);
 701                 if (GetServerStatus(Buf, &Status) == 3) {
 702                         serv_printf("PASS %s", ChrPtr(WC->Hdr->c_password));
 703                         StrBuf_ServGetln(Buf);
 704                         if (GetServerStatus(Buf, NULL) == 2) {
 705                                 become_logged_in(WC->Hdr->c_username, WC->Hdr->c_password, Buf);
 706                         }
 707                         else {
 708                                 /* Should only display when password is wrong */
 709                                 WC->ImportantMsg = NewStrBufPlain(ChrPtr(Buf) + 4, StrLength(Buf) - 4);
 710                                 authorization_required();
 711                                 FreeStrBuf(&Buf);
 712                                 goto SKIP_ALL_THIS_CRAP;
 713                         }
 714                 }
 715                 else if (Status == 541) {
 716                         WC->logged_in = 1;
 717                 }
 718         }
 719
 720         xhttp = (WC->Hdr->HR.eReqType != eGET) &&
 721                 (WC->Hdr->HR.eReqType != ePOST) &&
 722                 (WC->Hdr->HR.eReqType != eHEAD);
 723
 724         /*
 725          * If a 'go' (or 'gotofirst') parameter has been specified, attempt to goto that room
 726          * prior to doing anything else.
 727          */
 728         if (havebstr("go")) {
 729                 int ret;
 730                 if (verbose)
 731                         syslog(LOG_DEBUG, "Explicit room selection: %s", bstr("go"));
 732                 ret = gotoroom(sbstr("go"));    /* do quietly to avoid session output! */
 733                 if ((ret/100) != 2) {
 734                         if (verbose)
 735                                 syslog(LOG_DEBUG, "Unable to change to [%s]; Reason: %d", bstr("go"), ret);
 736                 }
 737         }
 738         else if (havebstr("gotofirst")) {
 739                 int ret;
 740                 if (verbose)
 741                         syslog(LOG_DEBUG, "Explicit room selection: %s", bstr("gotofirst"));
 742                 ret = gotoroom(sbstr("gotofirst"));     /* do quietly to avoid session output! */
 743                 if ((ret/100) != 2) {
 744                         syslog(LOG_INFO, "Unable to change to [%s]; Reason: %d", bstr("gotofirst"), ret);
 745                 }
 746         }
 747
 748         /*
 749          * If we aren't in any room yet, but we have cookie data telling us where we're
 750          * supposed to be, and 'go' was not specified, then go there.
 751          */
 752         else if ( (StrLength(WC->CurRoom.name) == 0) && ( (StrLength(WC->Hdr->c_roomname) > 0) )) {
 753                 int ret;
 754
 755                 if (verbose)
 756                         syslog(LOG_DEBUG, "We are in '%s' but cookie indicates '%s', going there...",
 757                                ChrPtr(WC->CurRoom.name),
 758                                ChrPtr(WC->Hdr->c_roomname)
 759                 );
 760                 ret = gotoroom(WC->Hdr->c_roomname);    /* do quietly to avoid session output! */
 761                 if ((ret/100) != 2) {
 762                         if (verbose)
 763                                 syslog(LOG_DEBUG, "COOKIEGOTO: Unable to change to [%s]; Reason: %d",
 764                                        ChrPtr(WC->Hdr->c_roomname), ret);
 765                 }
 766         }
 767
 768         if (WC->Hdr->HR.Handler != NULL) {
 769                 if (    (!WC->logged_in)
 770                         && ((WC->Hdr->HR.Handler->Flags & ANONYMOUS) == 0)
 771                         && (WC->serv_info != NULL)
 772                         && (WC->serv_info->serv_supports_guest == 0)
 773                 ) {
 774                         display_login();
 775                 }
 776                 else {
 777                         if ((WC->Hdr->HR.Handler->Flags & AJAX) != 0) {
 778                                 begin_ajax_response();
 779                         }
 780                         WC->Hdr->HR.Handler->F();
 781                         if ((WC->Hdr->HR.Handler->Flags & AJAX) != 0) {
 782                                 end_ajax_response();
 783                         }
 784                 }
 785         }
 786         /* When all else fails, display the default landing page or a main menu. */
 787         else {
 788                 /*
 789                  * ordinary browser users get a nice login screen, DAV etc. requsets
 790                  * are given a 401 so they can handle it appropriate.
 791                  */
 792                 if (!WC->logged_in)  {
 793                         if (xhttp) {
 794                                 authorization_required();
 795                         }
 796                         else {
 797                                 display_default_landing_page();
 798                         }
 799                 }
 800                 /*
 801                  * Toplevel dav requests? or just a flat browser request?
 802                  */
 803                 else {
 804                         if (xhttp) {
 805                                 dav_main();
 806                         }
 807                         else {
 808                                 display_main_menu();
 809                         }
 810                 }
 811         }
 812
 813 SKIP_ALL_THIS_CRAP:
 814         FreeStrBuf(&Buf);
 815         fflush(stdout);
 816 }
 817
 818
 819
 820 /*
 821  * Display the appropriate landing page for this site.
 822  */
 823 void display_default_landing_page(void) {
 824         if (WC && WC->serv_info && WC->serv_info->serv_supports_guest) {
 825                 /* default action */
 826
 827                 if (havebstr("go")) {
 828                         if (verbose)
 829                                 syslog(LOG_DEBUG, "Explicit room selection: %s", bstr("go"));
 830                         smart_goto(sbstr("go"));
 831                 }
 832                 else if (default_landing_page) {
 833                         http_redirect(default_landing_page);
 834                 }
 835                 else {
 836                         StrBuf *teh_lobby = NewStrBufPlain(HKEY("_BASEROOM_"));
 837                         smart_goto(teh_lobby);
 838                         FreeStrBuf(&teh_lobby);
 839                 }
 840         }
 841         else {
 842                 display_login();
 843         }
 844 }
 845
 846
 847 /*
 848  * Replacement for sleep() that uses select() in order to avoid SIGALRM
 849  */
 850 void sleeeeeeeeeep(int seconds)
 851 {
 852         struct timeval tv;
 853
 854         tv.tv_sec = seconds;
 855         tv.tv_usec = 0;
 856         select(0, NULL, NULL, NULL, &tv);
 857 }
 858
 859 int Conditional_IS_HTTPS(StrBuf *Target, WCTemplputParams *TP)
 860 {
 861         return is_https != 0;
 862 }
 863
 864 void AppendImportantMessage(const char *pch, long len)
 865 {
 866
 867         if (StrLength(WC->ImportantMsg) > 0) {
 868                 StrBufAppendBufPlain(WC->ImportantMsg, HKEY("\n"), 0);
 869         }
 870
 871         StrBufAppendBufPlain(WC->ImportantMsg, pch, len, 0);
 872 }
 873
 874 int ConditionalImportantMesage(StrBuf *Target, WCTemplputParams *TP)
 875 {
 876         if (WC != NULL) {
 877                 return (StrLength(WC->ImportantMsg) > 0);
 878         }
 879         else {
 880                 return 0;
 881         }
 882 }
 883
 884 void tmplput_importantmessage(StrBuf *Target, WCTemplputParams *TP)
 885 {
 886
 887         if (WC != NULL) {
 888                 if (StrLength(WC->ImportantMsg) > 0) {
 889                         StrBufAppendTemplate(Target, TP, WC->ImportantMsg, 0);
 890                 }
 891         }
 892 }
 893
 894 void tmplput_trailing_javascript(StrBuf *Target, WCTemplputParams *TP)
 895 {
 896
 897         if (WC != NULL) {
 898                 StrBufAppendTemplate(Target, TP, WC->trailing_javascript, 0);
 899         }
 900 }
 901
 902 void tmplput_csslocal(StrBuf *Target, WCTemplputParams *TP)
 903 {
 904         StrBufAppendBuf(Target,
 905                         csslocal, 0);
 906 }
 907
 908 void tmplput_packagestring(StrBuf *Target, WCTemplputParams *TP) {
 909         StrBufAppendBufPlain(Target, HKEY(PACKAGE_STRING), 0);
 910 }
 911
 912 extern char static_local_dir[PATH_MAX];
 913
 914
 915 void
 916 InitModule_WEBCIT
 917 (void)
 918 {
 919         char dir[SIZ];
 920         WebcitAddUrlHandler(HKEY("blank"), "", 0, blank_page, ANONYMOUS|COOKIEUNNEEDED|ISSTATIC);
 921         WebcitAddUrlHandler(HKEY("landing"), "", 0, display_default_landing_page, ANONYMOUS|COOKIEUNNEEDED);
 922         WebcitAddUrlHandler(HKEY("do_template"), "", 0, url_do_template, ANONYMOUS);
 923         WebcitAddUrlHandler(HKEY("sslg"), "", 0, seconds_since_last_gexp, AJAX|LOGCHATTY);
 924         WebcitAddUrlHandler(HKEY("ajax_servcmd"), "", 0, ajax_servcmd, 0);
 925         WebcitAddUrlHandler(HKEY("webcit"), "", 0, blank_page, URLNAMESPACE);
 926         WebcitAddUrlHandler(HKEY("push"), "", 0, push_destination, AJAX);
 927         WebcitAddUrlHandler(HKEY("pop"), "", 0, pop_destination, 0);
 928
 929         WebcitAddUrlHandler(HKEY("401"), "", 0, authorization_required, ANONYMOUS|COOKIEUNNEEDED);
 930         RegisterConditional("COND:IMPMSG", 0, ConditionalImportantMesage, CTX_NONE);
 931         RegisterConditional("COND:REST:DEPTH", 0, Conditional_REST_DEPTH, CTX_NONE);
 932         RegisterConditional("COND:IS_HTTPS", 0, Conditional_IS_HTTPS, CTX_NONE);
 933
 934         RegisterNamespace("CSSLOCAL", 0, 0, tmplput_csslocal, NULL, CTX_NONE);
 935         RegisterNamespace("IMPORTANTMESSAGE", 0, 1, tmplput_importantmessage, NULL, CTX_NONE);
 936         RegisterNamespace("TRAILING_JAVASCRIPT", 0, 0, tmplput_trailing_javascript, NULL, CTX_NONE);
 937         RegisterNamespace("URL:DISPLAYNAME", 0, 1, tmplput_HANDLER_DISPLAYNAME, NULL, CTX_NONE);
 938         RegisterNamespace("PACKAGESTRING", 0, 1, tmplput_packagestring, NULL, CTX_NONE);
 939
 940
 941         snprintf(dir, SIZ, "%s/webcit.css", static_local_dir);
 942         if (!access(dir, R_OK)) {
 943                 syslog(LOG_INFO, "Using local Stylesheet [%s]", dir);
 944                 csslocal = NewStrBufPlain(HKEY("<link href=\"static.local/webcit.css\" rel=\"stylesheet\" type=\"text/css\" />"));
 945         }
 946         else
 947                 syslog(LOG_INFO, "No Site-local Stylesheet [%s] installed.", dir);
 948
 949 }
 950
 951 void
 952 ServerStartModule_WEBCIT
 953 (void)
 954 {
 955         HandlerHash = NewHash(1, NULL);
 956 }
 957
 958
 959 void
 960 ServerShutdownModule_WEBCIT
 961 (void)
 962 {
 963         FreeStrBuf(&csslocal);
 964         DeleteHash(&HandlerHash);
 965 }
 966
 967
 968
 969 void
 970 SessionNewModule_WEBCIT
 971 (wcsession *sess)
 972 {
 973         sess->ImportantMsg = NewStrBuf();
 974         sess->WBuf = NewStrBufPlain(NULL, SIZ * 4);
 975         sess->HBuf = NewStrBufPlain(NULL, SIZ / 4);
 976 }
 977
 978 void
 979 SessionDetachModule_WEBCIT
 980 (wcsession *sess)
 981 {
 982         DeleteHash(&sess->Directory);
 983
 984         FreeStrBuf(&sess->upload);
 985         sess->upload_length = 0;
 986
 987         FreeStrBuf(&sess->trailing_javascript);
 988
 989         if (StrLength(sess->WBuf) > SIZ * 30) /* Bigger than 120K? release. */
 990         {
 991                 FreeStrBuf(&sess->WBuf);
 992                 sess->WBuf = NewStrBuf();
 993         }
 994         else
 995                 FlushStrBuf(sess->WBuf);
 996         FlushStrBuf(sess->HBuf);
 997         if (StrLength(sess->ImportantMsg) > 0) {
 998                 FlushStrBuf(sess->ImportantMsg);
 999         }
1000
1001 }
1002
1003 void
1004 SessionDestroyModule_WEBCIT
1005 (wcsession *sess)
1006 {
1007         FreeStrBuf(&sess->WBuf);
1008         FreeStrBuf(&sess->HBuf);
1009         FreeStrBuf(&sess->ImportantMsg);
1010         FreeStrBuf(&sess->PushedDestination);
1011 }
1012