webcit/context_loop.c

   1 /*
   2  * This is the other half of the webserver.  It handles the task of hooking
   3  * up HTTP requests with the sessions they belong to, using HTTP cookies to
   4  * keep track of things.  If the HTTP request doesn't belong to any currently
   5  * active session, a new session is started.
   6  *
   7  * Copyright (c) 1996-2011 by the citadel.org team
   8  *
   9  * This program is open source software.  You can redistribute it and/or
  10  * modify it under the terms of the GNU General Public License as
  11  * published by the Free Software Foundation; either version 3 of the
  12  * License, or (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  22  */
  23
  24 #include "webcit.h"
  25 #include "webserver.h"
  26 #include "modules_init.h"
  27
  28 /* Only one thread may manipulate SessionList at a time... */
  29 pthread_mutex_t SessionListMutex;
  30
  31 wcsession *SessionList = NULL;  /* Linked list of all webcit sessions */
  32
  33 pthread_key_t MyConKey;         /* TSD key for MySession() */
  34 HashList *HttpReqTypes = NULL;
  35 HashList *HttpHeaderHandler = NULL;
  36 extern HashList *HandlerHash;
  37
  38 /* the following two values start at 1 because the initial parent thread counts as one. */
  39 int num_threads_existing = 1;           /* Number of worker threads which exist. */
  40 int num_threads_executing = 1;          /* Number of worker threads currently executing. */
  41
  42 void DestroyHttpHeaderHandler(void *V)
  43 {
  44         OneHttpHeader *pHdr;
  45         pHdr = (OneHttpHeader*) V;
  46         FreeStrBuf(&pHdr->Val);
  47         free(pHdr);
  48 }
  49
  50 void shutdown_sessions(void)
  51 {
  52         wcsession *sptr;
  53
  54         for (sptr = SessionList; sptr != NULL; sptr = sptr->next) {
  55                         sptr->killthis = 1;
  56         }
  57 }
  58
  59 void do_housekeeping(void)
  60 {
  61         wcsession *sptr, *ss;
  62         wcsession *sessions_to_kill = NULL;
  63
  64         /*
  65          * Lock the session list, moving any candidates for euthanasia into
  66          * a separate list.
  67          */
  68         CtdlLogResult(pthread_mutex_lock(&SessionListMutex));
  69         for (sptr = SessionList; sptr != NULL; sptr = sptr->next) {
  70
  71                 /* Kill idle sessions */
  72                 if ((time(NULL) - (sptr->lastreq)) > (time_t) WEBCIT_TIMEOUT) {
  73                         syslog(3, "Timeout session %d\n", sptr->wc_session);
  74                         sptr->killthis = 1;
  75                 }
  76
  77                 /* Remove sessions flagged for kill */
  78                 if (sptr->killthis) {
  79
  80                         /* remove session from linked list */
  81                         if (sptr == SessionList) {
  82                                 SessionList = SessionList->next;
  83                         }
  84                         else for (ss=SessionList;ss!=NULL;ss=ss->next) {
  85                                 if (ss->next == sptr) {
  86                                         ss->next = ss->next->next;
  87                                 }
  88                         }
  89
  90                         sptr->next = sessions_to_kill;
  91                         sessions_to_kill = sptr;
  92                 }
  93         }
  94         CtdlLogResult(pthread_mutex_unlock(&SessionListMutex));
  95
  96         /*
  97          * Now free up and destroy the culled sessions.
  98          */
  99         while (sessions_to_kill != NULL) {
 100                 syslog(3, "Destroying session %d\n", sessions_to_kill->wc_session);
 101                 sptr = sessions_to_kill->next;
 102                 session_destroy_modules(&sessions_to_kill);
 103                 sessions_to_kill = sptr;
 104         }
 105 }
 106
 107 /*
 108  * Check the size of our thread pool.  If all threads are executing, spawn another.
 109  */
 110 void check_thread_pool_size(void)
 111 {
 112         if (time_to_die) return;                /* don't expand the thread pool during shutdown */
 113
 114         begin_critical_section(S_SPAWNER);      /* only one of these should run at a time */
 115         if (
 116                 (num_threads_executing >= num_threads_existing)
 117                 && (num_threads_existing < MAX_WORKER_THREADS)
 118         ) {
 119                 syslog(3, "%d of %d threads are executing.  Adding another worker thread.\n",
 120                         num_threads_executing,
 121                         num_threads_existing
 122                 );
 123                 spawn_another_worker_thread();
 124         }
 125         end_critical_section(S_SPAWNER);
 126 }
 127
 128
 129 /*
 130  * Wake up occasionally and clean house
 131  */
 132 void housekeeping_loop(void)
 133 {
 134         while (1) {
 135                 sleeeeeeeeeep(HOUSEKEEPING);
 136                 do_housekeeping();
 137         }
 138 }
 139
 140
 141 /*
 142  * Create a Session id
 143  * Generate a unique WebCit session ID (which is not the same thing as the
 144  * Citadel session ID).
 145  */
 146 int GenerateSessionID(void)
 147 {
 148         static int seq = (-1);
 149
 150         if (seq < 0) {
 151                 seq = (int) time(NULL);
 152         }
 153
 154         return ++seq;
 155 }
 156
 157 wcsession *FindSession(wcsession **wclist, ParsedHttpHdrs *Hdr, pthread_mutex_t *ListMutex)
 158 {
 159         wcsession *sptr = NULL;
 160         wcsession *TheSession = NULL;
 161
 162         if (Hdr->HR.got_auth == AUTH_BASIC) {
 163                 GetAuthBasic(Hdr);
 164         }
 165
 166         CtdlLogResult(pthread_mutex_lock(ListMutex));
 167         for (sptr = *wclist; ((sptr != NULL) && (TheSession == NULL)); sptr = sptr->next) {
 168
 169                 /* If HTTP-AUTH, look for a session with matching credentials */
 170                 switch (Hdr->HR.got_auth)
 171                 {
 172                 case AUTH_BASIC:
 173                         if ( (Hdr->HR.SessionKey != sptr->SessionKey))
 174                                 continue;
 175                         if ((!strcasecmp(ChrPtr(Hdr->c_username), ChrPtr(sptr->wc_username))) &&
 176                             (!strcasecmp(ChrPtr(Hdr->c_password), ChrPtr(sptr->wc_password))) ) {
 177                                 TheSession = sptr;
 178                         }
 179                         if (TheSession == NULL)
 180                                 syslog(1, "found sessionkey [%d], but credentials for [%s|%s] didn't match\n",
 181                                         Hdr->HR.SessionKey,ChrPtr(Hdr->c_username), ChrPtr(sptr->wc_username));
 182                         break;
 183                 case AUTH_COOKIE:
 184                         /* If cookie-session, look for a session with matching session ID */
 185                         if ( (Hdr->HR.desired_session != 0) &&
 186                              (sptr->wc_session == Hdr->HR.desired_session)) {
 187                                 TheSession = sptr;
 188                         }
 189                         break;
 190                 case NO_AUTH:
 191                         break;
 192                 }
 193         }
 194         CtdlLogResult(pthread_mutex_unlock(ListMutex));
 195         if (TheSession == NULL)
 196                 syslog(1, "didn't find sessionkey [%d] for user [%s]\n",
 197                         Hdr->HR.SessionKey, ChrPtr(Hdr->c_username));
 198         return TheSession;
 199 }
 200
 201 wcsession *CreateSession(int Lockable, int Static, wcsession **wclist, ParsedHttpHdrs *Hdr, pthread_mutex_t *ListMutex)
 202 {
 203         wcsession *TheSession;
 204         TheSession = (wcsession *) malloc(sizeof(wcsession));
 205         memset(TheSession, 0, sizeof(wcsession));
 206         TheSession->Hdr = Hdr;
 207         TheSession->SessionKey = Hdr->HR.SessionKey;
 208         TheSession->serv_sock = (-1);
 209
 210         pthread_setspecific(MyConKey, (void *)TheSession);
 211
 212         /* If we're recreating a session that expired, it's best to give it the same
 213          * session number that it had before.  The client browser ought to pick up
 214          * the new session number and start using it, but in some rare situations it
 215          * doesn't, and that's a Bad Thing because it causes lots of spurious sessions
 216          * to get created.
 217          */
 218         if (Hdr->HR.desired_session == 0) {
 219                 TheSession->wc_session = GenerateSessionID();
 220                 syslog(3, "Created new session %d", TheSession->wc_session);
 221         }
 222         else {
 223                 TheSession->wc_session = Hdr->HR.desired_session;
 224                 syslog(3, "Re-created session %d", TheSession->wc_session);
 225         }
 226         Hdr->HR.Static = Static;
 227         session_new_modules(TheSession);
 228
 229         if (Lockable) {
 230                 pthread_mutex_init(&TheSession->SessionMutex, NULL);
 231
 232                 if (ListMutex != NULL)
 233                         CtdlLogResult(pthread_mutex_lock(ListMutex));
 234
 235                 if (wclist != NULL) {
 236                         TheSession->nonce = rand();
 237                         TheSession->next = *wclist;
 238                         *wclist = TheSession;
 239                 }
 240                 if (ListMutex != NULL)
 241                         CtdlLogResult(pthread_mutex_unlock(ListMutex));
 242         }
 243         return TheSession;
 244 }
 245
 246
 247 /* If it's a "force 404" situation then display the error and bail. */
 248 void do_404(void)
 249 {
 250         hprintf("HTTP/1.1 404 Not found\r\n");
 251         hprintf("Content-Type: text/plain\r\n");
 252         wc_printf("Not found\r\n");
 253         end_burst();
 254 }
 255
 256 int ReadHttpSubject(ParsedHttpHdrs *Hdr, StrBuf *Line, StrBuf *Buf)
 257 {
 258         const char *Args;
 259         void *vLine, *vHandler;
 260         const char *Pos = NULL;
 261
 262
 263         Hdr->HR.ReqLine = Line;
 264         /* The requesttype... GET, POST... */
 265         StrBufExtract_token(Buf, Hdr->HR.ReqLine, 0, ' ');
 266         if (GetHash(HttpReqTypes, SKEY(Buf), &vLine) &&
 267             (vLine != NULL))
 268         {
 269                 Hdr->HR.eReqType = *(long*)vLine;
 270         }
 271         else {
 272                 Hdr->HR.eReqType = eGET;
 273                 return 1;
 274         }
 275         StrBufCutLeft(Hdr->HR.ReqLine, StrLength(Buf) + 1);
 276
 277         /* the HTTP Version... */
 278         StrBufExtract_token(Buf, Hdr->HR.ReqLine, 1, ' ');
 279         StrBufCutRight(Hdr->HR.ReqLine, StrLength(Buf) + 1);
 280
 281         if (StrLength(Buf) == 0) {
 282                 Hdr->HR.eReqType = eGET;
 283                 return 1;
 284         }
 285
 286         StrBufAppendBuf(Hdr->this_page, Hdr->HR.ReqLine, 0);
 287
 288         /* chop Filename / query arguments */
 289         Args = strchr(ChrPtr(Hdr->HR.ReqLine), '?');
 290         if (Args == NULL) /* whe're not that picky about params... TODO: this will spoil '&' in filenames.*/
 291                 Args = strchr(ChrPtr(Hdr->HR.ReqLine), '&');
 292         if (Args != NULL) {
 293                 Args ++; /* skip the ? */
 294                 StrBufPlain(Hdr->PlainArgs,
 295                             Args,
 296                             StrLength(Hdr->HR.ReqLine) -
 297                             (Args - ChrPtr(Hdr->HR.ReqLine)));
 298                 StrBufCutAt(Hdr->HR.ReqLine, 0, Args - 1);
 299         } /* don't parse them yet, maybe we don't even care... */
 300
 301         /* now lookup what we are going to do with this... */
 302         /* skip first slash */
 303         StrBufExtract_NextToken(Buf, Hdr->HR.ReqLine, &Pos, '/');
 304         do {
 305                 StrBufExtract_NextToken(Buf, Hdr->HR.ReqLine, &Pos, '/');
 306
 307                 GetHash(HandlerHash, SKEY(Buf), &vHandler),
 308                 Hdr->HR.Handler = (WebcitHandler*) vHandler;
 309                 if (Hdr->HR.Handler == NULL)
 310                         break;
 311                 /*
 312                  * If the request is prefixed by "/webcit" then chop that off.  This
 313                  * allows a front end web server to forward all /webcit requests to us
 314                  * while still using the same web server port for other things.
 315                  */
 316                 if ((Hdr->HR.Handler->Flags & URLNAMESPACE) != 0)
 317                         continue;
 318                 break;
 319         } while (1);
 320         /* remove the handlername from the URL */
 321         if ((Pos != NULL) && (Pos != StrBufNOTNULL)){
 322                 StrBufCutLeft(Hdr->HR.ReqLine,
 323                               Pos - ChrPtr(Hdr->HR.ReqLine));
 324         }
 325
 326         if (Hdr->HR.Handler != NULL) {
 327                 if ((Hdr->HR.Handler->Flags & BOGUS) != 0)
 328                         return 1;
 329                 Hdr->HR.DontNeedAuth = (
 330                         ((Hdr->HR.Handler->Flags & ISSTATIC) != 0) ||
 331                         ((Hdr->HR.Handler->Flags & ANONYMOUS) != 0)
 332                         );
 333         }
 334         else {
 335                 Hdr->HR.DontNeedAuth = 1; /* Flat request? show him the login screen... */
 336         }
 337
 338         return 0;
 339 }
 340
 341 int AnalyseHeaders(ParsedHttpHdrs *Hdr)
 342 {
 343         OneHttpHeader *pHdr;
 344         void *vHdr;
 345         long HKLen;
 346         const char *HashKey;
 347         HashPos *at = GetNewHashPos(Hdr->HTTPHeaders, 0);
 348
 349         while (GetNextHashPos(Hdr->HTTPHeaders, at, &HKLen, &HashKey, &vHdr) &&
 350                (vHdr != NULL)) {
 351                 pHdr = (OneHttpHeader *)vHdr;
 352                 if (pHdr->HaveEvaluator)
 353                         pHdr->H(pHdr->Val, Hdr);
 354
 355         }
 356         DeleteHashPos(&at);
 357         return 0;
 358 }
 359
 360 /*const char *nix(void *vptr) {return ChrPtr( (StrBuf*)vptr);}*/
 361
 362 /*
 363  * Read in the request
 364  */
 365 int ReadHTTPRequest (ParsedHttpHdrs *Hdr)
 366 {
 367         const char *pch, *pchs, *pche;
 368         OneHttpHeader *pHdr;
 369         StrBuf *Line, *LastLine, *HeaderName;
 370         int nLine = 0;
 371         void *vF;
 372         int isbogus = 0;
 373
 374         HeaderName = NewStrBuf();
 375         LastLine = NULL;
 376         do {
 377                 nLine ++;
 378                 Line = NewStrBufPlain(NULL, SIZ / 4);
 379
 380                 if (ClientGetLine(Hdr, Line) < 0) return 1;
 381
 382                 if (StrLength(Line) == 0) {
 383                         FreeStrBuf(&Line);
 384                         continue;
 385                 }
 386                 if (nLine == 1) {
 387                         Hdr->HTTPHeaders = NewHash(1, NULL);
 388                         pHdr = (OneHttpHeader*) malloc(sizeof(OneHttpHeader));
 389                         memset(pHdr, 0, sizeof(OneHttpHeader));
 390                         pHdr->Val = Line;
 391                         Put(Hdr->HTTPHeaders, HKEY("GET /"), pHdr, DestroyHttpHeaderHandler);
 392                         syslog(9, "%s\n", ChrPtr(Line));
 393                         isbogus = ReadHttpSubject(Hdr, Line, HeaderName);
 394                         if (isbogus) break;
 395                         continue;
 396                 }
 397
 398                 /* Do we need to Unfold? */
 399                 if ((LastLine != NULL) &&
 400                     (isspace(*ChrPtr(Line)))) {
 401                         pch = pchs = ChrPtr(Line);
 402                         pche = pchs + StrLength(Line);
 403                         while (isspace(*pch) && (pch < pche))
 404                                 pch ++;
 405                         StrBufCutLeft(Line, pch - pchs);
 406                         StrBufAppendBuf(LastLine, Line, 0);
 407
 408                         FreeStrBuf(&Line);
 409                         continue;
 410                 }
 411
 412                 StrBufSanitizeAscii(Line, '§');
 413                 StrBufExtract_token(HeaderName, Line, 0, ':');
 414
 415                 pchs = ChrPtr(Line);
 416                 pche = pchs + StrLength(Line);
 417                 pch = pchs + StrLength(HeaderName) + 1;
 418                 pche = pchs + StrLength(Line);
 419                 while ((pch < pche) && isspace(*pch))
 420                         pch ++;
 421                 StrBufCutLeft(Line, pch - pchs);
 422
 423                 StrBufUpCase(HeaderName);
 424
 425                 pHdr = (OneHttpHeader*) malloc(sizeof(OneHttpHeader));
 426                 memset(pHdr, 0, sizeof(OneHttpHeader));
 427                 pHdr->Val = Line;
 428
 429                 if (GetHash(HttpHeaderHandler, SKEY(HeaderName), &vF) &&
 430                     (vF != NULL))
 431                 {
 432                         OneHttpHeader *FHdr = (OneHttpHeader*) vF;
 433                         pHdr->H = FHdr->H;
 434                         pHdr->HaveEvaluator = 1;
 435                 }
 436                 Put(Hdr->HTTPHeaders, SKEY(HeaderName), pHdr, DestroyHttpHeaderHandler);
 437                 LastLine = Line;
 438         } while (Line != NULL);
 439
 440         FreeStrBuf(&HeaderName);
 441
 442         return isbogus;
 443 }
 444
 445 void OverrideRequest(ParsedHttpHdrs *Hdr, const char *Line, long len)
 446 {
 447         StrBuf *Buf = NewStrBuf();
 448
 449         if (Hdr->HR.ReqLine != NULL) {
 450                 FlushStrBuf(Hdr->HR.ReqLine);
 451                 StrBufPlain(Hdr->HR.ReqLine, Line, len);
 452         }
 453         else {
 454                 Hdr->HR.ReqLine = NewStrBufPlain(Line, len);
 455         }
 456         ReadHttpSubject(Hdr, Hdr->HR.ReqLine, Buf);
 457
 458         FreeStrBuf(&Buf);
 459 }
 460
 461 /*
 462  * handle one request
 463  *
 464  * This loop gets called once for every HTTP connection made to WebCit.  At
 465  * this entry point we have an HTTP socket with a browser allegedly on the
 466  * other end, but we have not yet bound to a WebCit session.
 467  *
 468  * The job of this function is to locate the correct session and bind to it,
 469  * or create a session if necessary and bind to it, then run the WebCit
 470  * transaction loop.  Afterwards, we unbind from the session.  When this
 471  * function returns, the worker thread is then free to handle another
 472  * transaction.
 473  */
 474 void context_loop(ParsedHttpHdrs *Hdr)
 475 {
 476         int isbogus = 0;
 477         wcsession *TheSession;
 478         struct timeval tx_start;
 479         struct timeval tx_finish;
 480
 481         gettimeofday(&tx_start, NULL);          /* start a stopwatch for performance timing */
 482
 483         /*
 484          * Find out what it is that the web browser is asking for
 485          */
 486         isbogus = ReadHTTPRequest(Hdr);
 487
 488         Hdr->HR.dav_depth = 32767; /* TODO: find a general way to have non-0 defaults */
 489         if (!isbogus)
 490                 isbogus = AnalyseHeaders(Hdr);
 491
 492         if ((isbogus) ||
 493             ((Hdr->HR.Handler != NULL) &&
 494              ((Hdr->HR.Handler->Flags & BOGUS) != 0)))
 495         {
 496                 wcsession *Bogus;
 497
 498                 Bogus = CreateSession(0, 1, NULL, Hdr, NULL);
 499
 500                 do_404();
 501
 502                 syslog(9, "HTTP: 404 [%ld.%06ld] %s %s \n",
 503                         ((tx_finish.tv_sec*1000000 + tx_finish.tv_usec) - (tx_start.tv_sec*1000000 + tx_start.tv_usec)) / 1000000,
 504                         ((tx_finish.tv_sec*1000000 + tx_finish.tv_usec) - (tx_start.tv_sec*1000000 + tx_start.tv_usec)) % 1000000,
 505                         ReqStrs[Hdr->HR.eReqType],
 506                         ChrPtr(Hdr->this_page)
 507                         );
 508                 session_detach_modules(Bogus);
 509                 session_destroy_modules(&Bogus);
 510                 return;
 511         }
 512
 513         if ((Hdr->HR.Handler != NULL) && ((Hdr->HR.Handler->Flags & ISSTATIC) != 0))
 514         {
 515                 wcsession *Static;
 516                 Static = CreateSession(0, 1, NULL, Hdr, NULL);
 517
 518                 Hdr->HR.Handler->F();
 519
 520                 /* How long did this transaction take? */
 521                 gettimeofday(&tx_finish, NULL);
 522
 523                 syslog(9, "HTTP: 200 [%ld.%06ld] %s %s \n",
 524                         ((tx_finish.tv_sec*1000000 + tx_finish.tv_usec) - (tx_start.tv_sec*1000000 + tx_start.tv_usec)) / 1000000,
 525                         ((tx_finish.tv_sec*1000000 + tx_finish.tv_usec) - (tx_start.tv_sec*1000000 + tx_start.tv_usec)) % 1000000,
 526                         ReqStrs[Hdr->HR.eReqType],
 527                         ChrPtr(Hdr->this_page)
 528                 );
 529                 session_detach_modules(Static);
 530                 session_destroy_modules(&Static);
 531                 return;
 532         }
 533
 534         if (Hdr->HR.got_auth == AUTH_BASIC) {
 535                 CheckAuthBasic(Hdr);
 536         }
 537
 538         /*
 539          * See if there's an existing session open with the desired ID or user/pass
 540          */
 541         TheSession = FindSession(&SessionList, Hdr, &SessionListMutex);
 542
 543         /*
 544          * Create a new session if we have to
 545          */
 546         if (TheSession == NULL) {
 547                 TheSession = CreateSession(1, 0, &SessionList, Hdr, &SessionListMutex);
 548
 549                 if (    (StrLength(Hdr->c_username) == 0)
 550                         && (!Hdr->HR.DontNeedAuth)
 551                         && (Hdr->HR.Handler != NULL)
 552                         && ((XHTTP_COMMANDS & Hdr->HR.Handler->Flags) == XHTTP_COMMANDS)
 553                 ) {
 554                         OverrideRequest(Hdr, HKEY("GET /401 HTTP/1.0"));
 555                         Hdr->HR.prohibit_caching = 1;
 556                 }
 557
 558                 if (StrLength(Hdr->c_language) > 0) {
 559                         syslog(9, "Session cookie requests language '%s'\n", ChrPtr(Hdr->c_language));
 560                         set_selected_language(ChrPtr(Hdr->c_language));
 561                         go_selected_language();
 562                 }
 563         }
 564
 565         /*
 566          * A future improvement might be to check the session integrity
 567          * at this point before continuing.
 568          */
 569
 570         /*
 571          * Bind to the session and perform the transaction
 572          */
 573         CtdlLogResult(pthread_mutex_lock(&TheSession->SessionMutex));
 574         pthread_setspecific(MyConKey, (void *)TheSession);
 575
 576         TheSession->lastreq = time(NULL);                       /* log */
 577         TheSession->Hdr = Hdr;
 578
 579         session_attach_modules(TheSession);
 580         session_loop();                         /* do transaction */
 581
 582
 583         /* How long did this transaction take? */
 584         gettimeofday(&tx_finish, NULL);
 585
 586
 587         syslog(9, "HTTP: 200 [%ld.%06ld] %s %s \n",
 588                 ((tx_finish.tv_sec*1000000 + tx_finish.tv_usec) - (tx_start.tv_sec*1000000 + tx_start.tv_usec)) / 1000000,
 589                 ((tx_finish.tv_sec*1000000 + tx_finish.tv_usec) - (tx_start.tv_sec*1000000 + tx_start.tv_usec)) % 1000000,
 590                 ReqStrs[Hdr->HR.eReqType],
 591                 ChrPtr(Hdr->this_page)
 592         );
 593
 594         session_detach_modules(TheSession);
 595
 596         TheSession->Hdr = NULL;
 597         CtdlLogResult(pthread_mutex_unlock(&TheSession->SessionMutex));
 598 }
 599
 600 void tmplput_nonce(StrBuf *Target, WCTemplputParams *TP)
 601 {
 602         wcsession *WCC = WC;
 603         StrBufAppendPrintf(Target, "%ld",
 604                            (WCC != NULL)? WCC->nonce:0);
 605 }
 606
 607 void tmplput_current_user(StrBuf *Target, WCTemplputParams *TP)
 608 {
 609         StrBufAppendTemplate(Target, TP, WC->wc_fullname, 0);
 610 }
 611
 612 void Header_HandleContentLength(StrBuf *Line, ParsedHttpHdrs *hdr)
 613 {
 614         hdr->HR.ContentLength = StrToi(Line);
 615 }
 616
 617 void Header_HandleContentType(StrBuf *Line, ParsedHttpHdrs *hdr)
 618 {
 619         hdr->HR.ContentType = Line;
 620 }
 621
 622
 623 void Header_HandleHost(StrBuf *Line, ParsedHttpHdrs *hdr)
 624 {
 625         if (hdr->HostHeader != NULL) {
 626                 FreeStrBuf(&hdr->HostHeader);
 627         }
 628         hdr->HostHeader = NewStrBuf();
 629         StrBufAppendPrintf(hdr->HostHeader, "%s://", (is_https ? "https" : "http") );
 630         StrBufAppendBuf(hdr->HostHeader, Line, 0);
 631 }
 632
 633 void Header_HandleXFFHost(StrBuf *Line, ParsedHttpHdrs *hdr)
 634 {
 635         if (!follow_xff) return;
 636
 637         if (hdr->HostHeader != NULL) {
 638                 FreeStrBuf(&hdr->HostHeader);
 639         }
 640
 641         hdr->HostHeader = NewStrBuf();
 642         StrBufAppendPrintf(hdr->HostHeader, "http://"); /* this is naive; do something about it */
 643         StrBufAppendBuf(hdr->HostHeader, Line, 0);
 644 }
 645
 646
 647 void Header_HandleXFF(StrBuf *Line, ParsedHttpHdrs *hdr)
 648 {
 649         hdr->HR.browser_host = Line;
 650
 651         while (StrBufNum_tokens(hdr->HR.browser_host, ',') > 1) {
 652                 StrBufRemove_token(hdr->HR.browser_host, 0, ',');
 653         }
 654         StrBufTrim(hdr->HR.browser_host);
 655 }
 656
 657 void Header_HandleIfModSince(StrBuf *Line, ParsedHttpHdrs *hdr)
 658 {
 659         hdr->HR.if_modified_since = httpdate_to_timestamp(Line);
 660 }
 661
 662 void Header_HandleAcceptEncoding(StrBuf *Line, ParsedHttpHdrs *hdr)
 663 {
 664         /*
 665          * Can we compress?
 666          */
 667         if (strstr(&ChrPtr(Line)[16], "gzip")) {
 668                 hdr->HR.gzip_ok = 1;
 669         }
 670 }
 671 const char *ReqStrs[eNONE] = {
 672         "GET",
 673         "POST",
 674         "OPTIONS",
 675         "PROPFIND",
 676         "PUT",
 677         "DELETE",
 678         "HEAD",
 679         "MOVE",
 680         "COPY"
 681 };
 682
 683 void
 684 ServerStartModule_CONTEXT
 685 (void)
 686 {
 687         long *v;
 688         HttpReqTypes = NewHash(1, NULL);
 689         HttpHeaderHandler = NewHash(1, NULL);
 690
 691         v = malloc(sizeof(long));
 692         *v = eGET;
 693         Put(HttpReqTypes, HKEY("GET"), v, NULL);
 694
 695         v = malloc(sizeof(long));
 696         *v = ePOST;
 697         Put(HttpReqTypes, HKEY("POST"), v, NULL);
 698
 699         v = malloc(sizeof(long));
 700         *v = eOPTIONS;
 701         Put(HttpReqTypes, HKEY("OPTIONS"), v, NULL);
 702
 703         v = malloc(sizeof(long));
 704         *v = ePROPFIND;
 705         Put(HttpReqTypes, HKEY("PROPFIND"), v, NULL);
 706
 707         v = malloc(sizeof(long));
 708         *v = ePUT;
 709         Put(HttpReqTypes, HKEY("PUT"), v, NULL);
 710
 711         v = malloc(sizeof(long));
 712         *v = eDELETE;
 713         Put(HttpReqTypes, HKEY("DELETE"), v, NULL);
 714
 715         v = malloc(sizeof(long));
 716         *v = eHEAD;
 717         Put(HttpReqTypes, HKEY("HEAD"), v, NULL);
 718
 719         v = malloc(sizeof(long));
 720         *v = eMOVE;
 721         Put(HttpReqTypes, HKEY("MOVE"), v, NULL);
 722
 723         v = malloc(sizeof(long));
 724         *v = eCOPY;
 725         Put(HttpReqTypes, HKEY("COPY"), v, NULL);
 726 }
 727
 728 void
 729 ServerShutdownModule_CONTEXT
 730 (void)
 731 {
 732         DeleteHash(&HttpReqTypes);
 733         DeleteHash(&HttpHeaderHandler);
 734 }
 735
 736 void RegisterHeaderHandler(const char *Name, long Len, Header_Evaluator F)
 737 {
 738         OneHttpHeader *pHdr;
 739         pHdr = (OneHttpHeader*) malloc(sizeof(OneHttpHeader));
 740         memset(pHdr, 0, sizeof(OneHttpHeader));
 741         pHdr->H = F;
 742         Put(HttpHeaderHandler, Name, Len, pHdr, DestroyHttpHeaderHandler);
 743 }
 744
 745
 746 void
 747 InitModule_CONTEXT
 748 (void)
 749 {
 750         RegisterHeaderHandler(HKEY("CONTENT-LENGTH"), Header_HandleContentLength);
 751         RegisterHeaderHandler(HKEY("CONTENT-TYPE"), Header_HandleContentType);
 752         RegisterHeaderHandler(HKEY("X-FORWARDED-HOST"), Header_HandleXFFHost); /* Apache way... */
 753         RegisterHeaderHandler(HKEY("X-REAL-IP"), Header_HandleXFFHost);        /* NGinX way... */
 754         RegisterHeaderHandler(HKEY("HOST"), Header_HandleHost);
 755         RegisterHeaderHandler(HKEY("X-FORWARDED-FOR"), Header_HandleXFF);
 756         RegisterHeaderHandler(HKEY("ACCEPT-ENCODING"), Header_HandleAcceptEncoding);
 757         RegisterHeaderHandler(HKEY("IF-MODIFIED-SINCE"), Header_HandleIfModSince);
 758
 759         RegisterNamespace("CURRENT_USER", 0, 1, tmplput_current_user, NULL, CTX_NONE);
 760         RegisterNamespace("NONCE", 0, 0, tmplput_nonce, NULL, 0);
 761
 762         WebcitAddUrlHandler(HKEY("404"), "", 0, do_404, ANONYMOUS|COOKIEUNNEEDED);
 763 /*
 764  * Look for commonly-found probes of malware such as worms, viruses, trojans, and Microsoft Office.
 765  * Short-circuit these requests so we don't have to send them through the full processing loop.
 766  */
 767         WebcitAddUrlHandler(HKEY("scripts"), "", 0, do_404, ANONYMOUS|BOGUS);           /* /root.exe - Worms and trojans and viruses, oh my! */
 768         WebcitAddUrlHandler(HKEY("c"), "", 0, do_404, ANONYMOUS|BOGUS);         /* /winnt */
 769         WebcitAddUrlHandler(HKEY("MSADC"), "", 0, do_404, ANONYMOUS|BOGUS);
 770         WebcitAddUrlHandler(HKEY("_vti"), "", 0, do_404, ANONYMOUS|BOGUS);              /* Broken Microsoft DAV implementation */
 771         WebcitAddUrlHandler(HKEY("MSOffice"), "", 0, do_404, ANONYMOUS|BOGUS);          /* Stoopid MSOffice thinks everyone is IIS */
 772         WebcitAddUrlHandler(HKEY("nonexistenshit"), "", 0, do_404, ANONYMOUS|BOGUS);    /* Exploit found in the wild January 2009 */
 773 }
 774
 775
 776 void
 777 HttpNewModule_CONTEXT
 778 (ParsedHttpHdrs *httpreq)
 779 {
 780         httpreq->PlainArgs = NewStrBufPlain(NULL, SIZ);
 781         httpreq->this_page = NewStrBufPlain(NULL, SIZ);
 782 }
 783
 784 void
 785 HttpDetachModule_CONTEXT
 786 (ParsedHttpHdrs *httpreq)
 787 {
 788         FlushStrBuf(httpreq->PlainArgs);
 789         FlushStrBuf(httpreq->HostHeader);
 790         FlushStrBuf(httpreq->this_page);
 791         FlushStrBuf(httpreq->PlainArgs);
 792         DeleteHash(&httpreq->HTTPHeaders);
 793         memset(&httpreq->HR, 0, sizeof(HdrRefs));
 794 }
 795
 796 void
 797 HttpDestroyModule_CONTEXT
 798 (ParsedHttpHdrs *httpreq)
 799 {
 800         FreeStrBuf(&httpreq->this_page);
 801         FreeStrBuf(&httpreq->PlainArgs);
 802         FreeStrBuf(&httpreq->this_page);
 803         FreeStrBuf(&httpreq->PlainArgs);
 804         FreeStrBuf(&httpreq->HostHeader);
 805         DeleteHash(&httpreq->HTTPHeaders);
 806
 807 }