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                         sptr->killthis = 1;
  74                 }
  75
  76                 /* Remove sessions flagged for kill */
  77                 if (sptr->killthis) {
  78
  79                         /** remove session from linked list */
  80                         if (sptr == SessionList) {
  81                                 SessionList = SessionList->next;
  82                         }
  83                         else for (ss=SessionList;ss!=NULL;ss=ss->next) {
  84                                 if (ss->next == sptr) {
  85                                         ss->next = ss->next->next;
  86                                 }
  87                         }
  88
  89                         sptr->next = sessions_to_kill;
  90                         sessions_to_kill = sptr;
  91                 }
  92         }
  93         CtdlLogResult(pthread_mutex_unlock(&SessionListMutex));
  94
  95         /*
  96          * Now free up and destroy the culled sessions.
  97          */
  98         while (sessions_to_kill != NULL) {
  99                 lprintf(3, "Destroying session %d\n", sessions_to_kill->wc_session);
 100                 pthread_mutex_lock(&sessions_to_kill->SessionMutex);
 101                 pthread_mutex_unlock(&sessions_to_kill->SessionMutex);
 102                 sptr = sessions_to_kill->next;
 103
 104                 session_destroy_modules(&sessions_to_kill);
 105                 sessions_to_kill = sptr;
 106         }
 107 }
 108
 109 /*
 110  * Check the size of our thread pool.  If all threads are executing, spawn another.
 111  */
 112 void check_thread_pool_size(void)
 113 {
 114         if (time_to_die) return;                /* don't expand the thread pool during shutdown */
 115
 116         begin_critical_section(S_SPAWNER);      /* only one of these should run at a time */
 117         if (
 118                 (num_threads_executing >= num_threads_existing)
 119                 && (num_threads_existing < MAX_WORKER_THREADS)
 120         ) {
 121                 lprintf(3, "%d of %d threads are executing.  Adding another worker thread.\n",
 122                         num_threads_executing,
 123                         num_threads_existing
 124                 );
 125                 spawn_another_worker_thread();
 126         }
 127         end_critical_section(S_SPAWNER);
 128 }
 129
 130
 131 /*
 132  * Wake up occasionally and clean house
 133  */
 134 void housekeeping_loop(void)
 135 {
 136         while (1) {
 137                 sleeeeeeeeeep(HOUSEKEEPING);
 138                 do_housekeeping();
 139         }
 140 }
 141
 142
 143 /*
 144  * Create a Session id
 145  * Generate a unique WebCit session ID (which is not the same thing as the
 146  * Citadel session ID).
 147  */
 148 int GenerateSessionID(void)
 149 {
 150         static int seq = (-1);
 151
 152         if (seq < 0) {
 153                 seq = (int) time(NULL);
 154         }
 155
 156         return ++seq;
 157 }
 158
 159 wcsession *FindSession(wcsession **wclist, ParsedHttpHdrs *Hdr, pthread_mutex_t *ListMutex)
 160 {
 161         wcsession *sptr = NULL;
 162         wcsession *TheSession = NULL;
 163
 164         if (Hdr->HR.got_auth == AUTH_BASIC) {
 165                 GetAuthBasic(Hdr);
 166         }
 167
 168         CtdlLogResult(pthread_mutex_lock(ListMutex));
 169         for (sptr = *wclist; ((sptr != NULL) && (TheSession == NULL)); sptr = sptr->next) {
 170
 171                 /* If HTTP-AUTH, look for a session with matching credentials */
 172                 switch (Hdr->HR.got_auth)
 173                 {
 174                 case AUTH_BASIC:
 175                         if ( (Hdr->HR.SessionKey != sptr->SessionKey))
 176                                 continue;
 177                         if ((!strcasecmp(ChrPtr(Hdr->c_username), ChrPtr(sptr->wc_username))) &&
 178                             (!strcasecmp(ChrPtr(Hdr->c_password), ChrPtr(sptr->wc_password))) ) {
 179                                 TheSession = sptr;
 180                         }
 181                         if (TheSession == NULL)
 182                                 lprintf(1, "found sessionkey [%ld], but credentials for [%s|%s] didn't match\n",
 183                                         Hdr->HR.SessionKey,ChrPtr(Hdr->c_username), ChrPtr(sptr->wc_username));
 184                         break;
 185                 case AUTH_COOKIE:
 186                         /* If cookie-session, look for a session with matching session ID */
 187                         if ( (Hdr->HR.desired_session != 0) &&
 188                              (sptr->wc_session == Hdr->HR.desired_session)) {
 189                                 TheSession = sptr;
 190                         }
 191                         break;
 192                 case NO_AUTH:
 193                         break;
 194                 }
 195         }
 196         CtdlLogResult(pthread_mutex_unlock(ListMutex));
 197         if (TheSession == NULL)
 198                 lprintf(1, "didn't find sessionkey [%ld] for user [%s]\n",
 199                         Hdr->HR.SessionKey,ChrPtr(Hdr->c_username));
 200         return TheSession;
 201 }
 202
 203 wcsession *CreateSession(int Lockable, int Static, wcsession **wclist, ParsedHttpHdrs *Hdr, pthread_mutex_t *ListMutex)
 204 {
 205         wcsession *TheSession;
 206         if (!Static)
 207                 lprintf(3, "Creating a new session\n");
 208         TheSession = (wcsession *) malloc(sizeof(wcsession));
 209         memset(TheSession, 0, sizeof(wcsession));
 210         TheSession->Hdr = Hdr;
 211         TheSession->SessionKey = Hdr->HR.SessionKey;
 212         TheSession->serv_sock = (-1);
 213
 214         pthread_setspecific(MyConKey, (void *)TheSession);
 215
 216         /* If we're recreating a session that expired, it's best to give it the same
 217          * session number that it had before.  The client browser ought to pick up
 218          * the new session number and start using it, but in some rare situations it
 219          * doesn't, and that's a Bad Thing because it causes lots of spurious sessions
 220          * to get created.
 221          */
 222         if (Hdr->HR.desired_session == 0) {
 223                 TheSession->wc_session = GenerateSessionID();
 224         }
 225         else {
 226                 TheSession->wc_session = Hdr->HR.desired_session;
 227         }
 228         Hdr->HR.Static = Static;
 229         session_new_modules(TheSession);
 230
 231         if (Lockable) {
 232                 pthread_mutex_init(&TheSession->SessionMutex, NULL);
 233
 234                 if (ListMutex != NULL)
 235                         CtdlLogResult(pthread_mutex_lock(ListMutex));
 236
 237                 if (wclist != NULL) {
 238                         TheSession->nonce = rand();
 239                         TheSession->next = *wclist;
 240                         *wclist = TheSession;
 241                 }
 242                 if (ListMutex != NULL)
 243                         CtdlLogResult(pthread_mutex_unlock(ListMutex));
 244         }
 245         return TheSession;
 246 }
 247
 248
 249 /* If it's a "force 404" situation then display the error and bail. */
 250 void do_404(void)
 251 {
 252         hprintf("HTTP/1.1 404 Not found\r\n");
 253         hprintf("Content-Type: text/plain\r\n");
 254         wc_printf("Not found\r\n");
 255         end_burst();
 256 }
 257
 258 int ReadHttpSubject(ParsedHttpHdrs *Hdr, StrBuf *Line, StrBuf *Buf)
 259 {
 260         const char *Args;
 261         void *vLine, *vHandler;
 262         const char *Pos = NULL;
 263
 264
 265         Hdr->HR.ReqLine = Line;
 266         /* The requesttype... GET, POST... */
 267         StrBufExtract_token(Buf, Hdr->HR.ReqLine, 0, ' ');
 268         if (GetHash(HttpReqTypes, SKEY(Buf), &vLine) &&
 269             (vLine != NULL))
 270         {
 271                 Hdr->HR.eReqType = *(long*)vLine;
 272         }
 273         else {
 274                 Hdr->HR.eReqType = eGET;
 275                 return 1;
 276         }
 277         StrBufCutLeft(Hdr->HR.ReqLine, StrLength(Buf) + 1);
 278
 279         /* the HTTP Version... */
 280         StrBufExtract_token(Buf, Hdr->HR.ReqLine, 1, ' ');
 281         StrBufCutRight(Hdr->HR.ReqLine, StrLength(Buf) + 1);
 282
 283         if (StrLength(Buf) == 0) {
 284                 Hdr->HR.eReqType = eGET;
 285                 return 1;
 286         }
 287
 288         StrBufAppendBuf(Hdr->this_page, Hdr->HR.ReqLine, 0);
 289
 290         /* chop Filename / query arguments */
 291         Args = strchr(ChrPtr(Hdr->HR.ReqLine), '?');
 292         if (Args == NULL) /* whe're not that picky about params... TODO: this will spoil '&' in filenames.*/
 293                 Args = strchr(ChrPtr(Hdr->HR.ReqLine), '&');
 294         if (Args != NULL) {
 295                 Args ++; /* skip the ? */
 296                 StrBufPlain(Hdr->PlainArgs,
 297                             Args,
 298                             StrLength(Hdr->HR.ReqLine) -
 299                             (Args - ChrPtr(Hdr->HR.ReqLine)));
 300                 StrBufCutAt(Hdr->HR.ReqLine, 0, Args - 1);
 301         } /* don't parse them yet, maybe we don't even care... */
 302
 303         /* now lookup what we are going to do with this... */
 304         /* skip first slash */
 305         StrBufExtract_NextToken(Buf, Hdr->HR.ReqLine, &Pos, '/');
 306         do {
 307                 StrBufExtract_NextToken(Buf, Hdr->HR.ReqLine, &Pos, '/');
 308
 309                 GetHash(HandlerHash, SKEY(Buf), &vHandler),
 310                 Hdr->HR.Handler = (WebcitHandler*) vHandler;
 311                 if (Hdr->HR.Handler == NULL)
 312                         break;
 313                 /*
 314                  * If the request is prefixed by "/webcit" then chop that off.  This
 315                  * allows a front end web server to forward all /webcit requests to us
 316                  * while still using the same web server port for other things.
 317                  */
 318                 if ((Hdr->HR.Handler->Flags & URLNAMESPACE) != 0)
 319                         continue;
 320                 break;
 321         } while (1);
 322         /* remove the handlername from the URL */
 323         if ((Pos != NULL) && (Pos != StrBufNOTNULL)){
 324                 StrBufCutLeft(Hdr->HR.ReqLine,
 325                               Pos - ChrPtr(Hdr->HR.ReqLine));
 326         }
 327
 328         if (Hdr->HR.Handler != NULL) {
 329                 if ((Hdr->HR.Handler->Flags & BOGUS) != 0)
 330                         return 1;
 331                 Hdr->HR.DontNeedAuth = (
 332                         ((Hdr->HR.Handler->Flags & ISSTATIC) != 0) ||
 333                         ((Hdr->HR.Handler->Flags & ANONYMOUS) != 0)
 334                         );
 335         }
 336         else {
 337                 Hdr->HR.DontNeedAuth = 1; /* Flat request? show him the login screen... */
 338         }
 339
 340         return 0;
 341 }
 342
 343 int AnalyseHeaders(ParsedHttpHdrs *Hdr)
 344 {
 345         OneHttpHeader *pHdr;
 346         void *vHdr;
 347         long HKLen;
 348         const char *HashKey;
 349         HashPos *at = GetNewHashPos(Hdr->HTTPHeaders, 0);
 350
 351         while (GetNextHashPos(Hdr->HTTPHeaders, at, &HKLen, &HashKey, &vHdr) &&
 352                (vHdr != NULL)) {
 353                 pHdr = (OneHttpHeader *)vHdr;
 354                 if (pHdr->HaveEvaluator)
 355                         pHdr->H(pHdr->Val, Hdr);
 356
 357         }
 358         DeleteHashPos(&at);
 359         return 0;
 360 }
 361
 362 /*const char *nix(void *vptr) {return ChrPtr( (StrBuf*)vptr);}*/
 363
 364 /*
 365  * Read in the request
 366  */
 367 int ReadHTTPRequest (ParsedHttpHdrs *Hdr)
 368 {
 369         const char *pch, *pchs, *pche;
 370         OneHttpHeader *pHdr;
 371         StrBuf *Line, *LastLine, *HeaderName;
 372         int nLine = 0;
 373         void *vF;
 374         int isbogus = 0;
 375
 376         HeaderName = NewStrBuf();
 377         LastLine = NULL;
 378         do {
 379                 nLine ++;
 380                 Line = NewStrBufPlain(NULL, SIZ / 4);
 381
 382                 if (ClientGetLine(Hdr, Line) < 0) return 1;
 383
 384                 if (StrLength(Line) == 0) {
 385                         FreeStrBuf(&Line);
 386                         continue;
 387                 }
 388                 if (nLine == 1) {
 389                         Hdr->HTTPHeaders = NewHash(1, NULL);
 390                         pHdr = (OneHttpHeader*) malloc(sizeof(OneHttpHeader));
 391                         memset(pHdr, 0, sizeof(OneHttpHeader));
 392                         pHdr->Val = Line;
 393                         Put(Hdr->HTTPHeaders, HKEY("GET /"), pHdr, DestroyHttpHeaderHandler);
 394                         lprintf(9, "%s\n", ChrPtr(Line));
 395                         isbogus = ReadHttpSubject(Hdr, Line, HeaderName);
 396                         if (isbogus) break;
 397                         continue;
 398                 }
 399
 400                 /* Do we need to Unfold? */
 401                 if ((LastLine != NULL) &&
 402                     (isspace(*ChrPtr(Line)))) {
 403                         pch = pchs = ChrPtr(Line);
 404                         pche = pchs + StrLength(Line);
 405                         while (isspace(*pch) && (pch < pche))
 406                                 pch ++;
 407                         StrBufCutLeft(Line, pch - pchs);
 408                         StrBufAppendBuf(LastLine, Line, 0);
 409
 410                         FreeStrBuf(&Line);
 411                         continue;
 412                 }
 413
 414                 StrBufSanitizeAscii(Line, '§');
 415                 StrBufExtract_token(HeaderName, Line, 0, ':');
 416
 417                 pchs = ChrPtr(Line);
 418                 pche = pchs + StrLength(Line);
 419                 pch = pchs + StrLength(HeaderName) + 1;
 420                 pche = pchs + StrLength(Line);
 421                 while ((pch < pche) && isspace(*pch))
 422                         pch ++;
 423                 StrBufCutLeft(Line, pch - pchs);
 424
 425                 StrBufUpCase(HeaderName);
 426
 427                 pHdr = (OneHttpHeader*) malloc(sizeof(OneHttpHeader));
 428                 memset(pHdr, 0, sizeof(OneHttpHeader));
 429                 pHdr->Val = Line;
 430
 431                 if (GetHash(HttpHeaderHandler, SKEY(HeaderName), &vF) &&
 432                     (vF != NULL))
 433                 {
 434                         OneHttpHeader *FHdr = (OneHttpHeader*) vF;
 435                         pHdr->H = FHdr->H;
 436                         pHdr->HaveEvaluator = 1;
 437                 }
 438                 Put(Hdr->HTTPHeaders, SKEY(HeaderName), pHdr, DestroyHttpHeaderHandler);
 439                 LastLine = Line;
 440         } while (Line != NULL);
 441
 442         FreeStrBuf(&HeaderName);
 443
 444         return isbogus;
 445 }
 446
 447 void OverrideRequest(ParsedHttpHdrs *Hdr, const char *Line, long len)
 448 {
 449         StrBuf *Buf = NewStrBuf();
 450
 451         if (Hdr->HR.ReqLine != NULL) {
 452                 FlushStrBuf(Hdr->HR.ReqLine);
 453                 StrBufPlain(Hdr->HR.ReqLine, Line, len);
 454         }
 455         else {
 456                 Hdr->HR.ReqLine = NewStrBufPlain(Line, len);
 457         }
 458         ReadHttpSubject(Hdr, Hdr->HR.ReqLine, Buf);
 459
 460         FreeStrBuf(&Buf);
 461 }
 462
 463 /*
 464  * handle one request
 465  *
 466  * This loop gets called once for every HTTP connection made to WebCit.  At
 467  * this entry point we have an HTTP socket with a browser allegedly on the
 468  * other end, but we have not yet bound to a WebCit session.
 469  *
 470  * The job of this function is to locate the correct session and bind to it,
 471  * or create a session if necessary and bind to it, then run the WebCit
 472  * transaction loop.  Afterwards, we unbind from the session.  When this
 473  * function returns, the worker thread is then free to handle another
 474  * transaction.
 475  */
 476 void context_loop(ParsedHttpHdrs *Hdr)
 477 {
 478         int isbogus = 0;
 479         wcsession *TheSession;
 480         struct timeval tx_start;
 481         struct timeval tx_finish;
 482
 483         gettimeofday(&tx_start, NULL);          /* start a stopwatch for performance timing */
 484
 485         /*
 486          * Find out what it is that the web browser is asking for
 487          */
 488         isbogus = ReadHTTPRequest(Hdr);
 489
 490         Hdr->HR.dav_depth = 32767; /* TODO: find a general way to have non-0 defaults */
 491         if (!isbogus)
 492                 isbogus = AnalyseHeaders(Hdr);
 493
 494         if ((isbogus) ||
 495             ((Hdr->HR.Handler != NULL) &&
 496              ((Hdr->HR.Handler->Flags & BOGUS) != 0)))
 497         {
 498                 wcsession *Bogus;
 499
 500                 Bogus = CreateSession(0, 1, NULL, Hdr, NULL);
 501
 502                 do_404();
 503
 504                 lprintf(9, "HTTP: 404 [%ld.%06ld] %s %s \n",
 505                         ((tx_finish.tv_sec*1000000 + tx_finish.tv_usec) - (tx_start.tv_sec*1000000 + tx_start.tv_usec)) / 1000000,
 506                         ((tx_finish.tv_sec*1000000 + tx_finish.tv_usec) - (tx_start.tv_sec*1000000 + tx_start.tv_usec)) % 1000000,
 507                         ReqStrs[Hdr->HR.eReqType],
 508                         ChrPtr(Hdr->this_page)
 509                         );
 510                 session_detach_modules(Bogus);
 511                 session_destroy_modules(&Bogus);
 512                 return;
 513         }
 514
 515         if ((Hdr->HR.Handler != NULL) && ((Hdr->HR.Handler->Flags & ISSTATIC) != 0))
 516         {
 517                 wcsession *Static;
 518                 Static = CreateSession(0, 1, NULL, Hdr, NULL);
 519
 520                 Hdr->HR.Handler->F();
 521
 522                 /* How long did this transaction take? */
 523                 gettimeofday(&tx_finish, NULL);
 524
 525 #ifdef TECH_PREVIEW
 526                 if ((Hdr->HR.Handler != NULL) ||
 527                     ((Hdr->HR.Handler->Flags & LOGCHATTY) == 0))
 528 #endif
 529                         lprintf(9, "HTTP: 200 [%ld.%06ld] %s %s \n",
 530                                 ((tx_finish.tv_sec*1000000 + tx_finish.tv_usec) - (tx_start.tv_sec*1000000 + tx_start.tv_usec)) / 1000000,
 531                                 ((tx_finish.tv_sec*1000000 + tx_finish.tv_usec) - (tx_start.tv_sec*1000000 + tx_start.tv_usec)) % 1000000,
 532                                 ReqStrs[Hdr->HR.eReqType],
 533                                 ChrPtr(Hdr->this_page)
 534                                 );
 535                 session_detach_modules(Static);
 536                 session_destroy_modules(&Static);
 537                 return;
 538         }
 539
 540         if (Hdr->HR.got_auth == AUTH_BASIC) {
 541                 CheckAuthBasic(Hdr);
 542         }
 543
 544         /*
 545          * See if there's an existing session open with the desired ID or user/pass
 546          */
 547         TheSession = FindSession(&SessionList, Hdr, &SessionListMutex);
 548
 549         /*
 550          * Create a new session if we have to
 551          */
 552         if (TheSession == NULL) {
 553                 TheSession = CreateSession(1, 0, &SessionList, Hdr, &SessionListMutex);
 554
 555                 if (    (StrLength(Hdr->c_username) == 0)
 556                         && (!Hdr->HR.DontNeedAuth)
 557                         && (Hdr->HR.Handler != NULL)
 558                         && ((XHTTP_COMMANDS & Hdr->HR.Handler->Flags) == XHTTP_COMMANDS)
 559                 ) {
 560                         OverrideRequest(Hdr, HKEY("GET /401 HTTP/1.0"));
 561                         Hdr->HR.prohibit_caching = 1;
 562                 }
 563
 564                 if (StrLength(Hdr->c_language) > 0) {
 565                         lprintf(9, "Session cookie requests language '%s'\n", ChrPtr(Hdr->c_language));
 566                         set_selected_language(ChrPtr(Hdr->c_language));
 567                         go_selected_language();
 568                 }
 569         }
 570
 571         /*
 572          * A future improvement might be to check the session integrity
 573          * at this point before continuing.
 574          */
 575
 576         /*
 577          * Bind to the session and perform the transaction
 578          */
 579         CtdlLogResult(pthread_mutex_lock(&TheSession->SessionMutex));
 580         pthread_setspecific(MyConKey, (void *)TheSession);
 581
 582         TheSession->lastreq = time(NULL);                       /* log */
 583         TheSession->Hdr = Hdr;
 584
 585         session_attach_modules(TheSession);
 586         session_loop();                         /* do transaction */
 587
 588
 589         /* How long did this transaction take? */
 590         gettimeofday(&tx_finish, NULL);
 591
 592
 593 #ifdef TECH_PREVIEW
 594         if ((Hdr->HR.Handler != NULL) &&
 595             ((Hdr->HR.Handler->Flags & LOGCHATTY) == 0))
 596 #endif
 597                 lprintf(9, "HTTP: 200 [%ld.%06ld] %s %s \n",
 598                         ((tx_finish.tv_sec*1000000 + tx_finish.tv_usec) - (tx_start.tv_sec*1000000 + tx_start.tv_usec)) / 1000000,
 599                         ((tx_finish.tv_sec*1000000 + tx_finish.tv_usec) - (tx_start.tv_sec*1000000 + tx_start.tv_usec)) % 1000000,
 600                         ReqStrs[Hdr->HR.eReqType],
 601                         ChrPtr(Hdr->this_page)
 602                         );
 603
 604         session_detach_modules(TheSession);
 605
 606         TheSession->Hdr = NULL;
 607         CtdlLogResult(pthread_mutex_unlock(&TheSession->SessionMutex));
 608 }
 609
 610 void tmplput_nonce(StrBuf *Target, WCTemplputParams *TP)
 611 {
 612         wcsession *WCC = WC;
 613         StrBufAppendPrintf(Target, "%ld",
 614                            (WCC != NULL)? WCC->nonce:0);
 615 }
 616
 617 void tmplput_current_user(StrBuf *Target, WCTemplputParams *TP)
 618 {
 619         StrBufAppendTemplate(Target, TP, WC->wc_fullname, 0);
 620 }
 621
 622 void Header_HandleContentLength(StrBuf *Line, ParsedHttpHdrs *hdr)
 623 {
 624         hdr->HR.ContentLength = StrToi(Line);
 625 }
 626
 627 void Header_HandleContentType(StrBuf *Line, ParsedHttpHdrs *hdr)
 628 {
 629         hdr->HR.ContentType = Line;
 630 }
 631
 632
 633 void Header_HandleHost(StrBuf *Line, ParsedHttpHdrs *hdr)
 634 {
 635         if (site_prefix == NULL) {
 636                 site_prefix = NewStrBuf();
 637                 StrBufAppendPrintf(site_prefix, "%s://", (is_https ? "https" : "http") );
 638                 StrBufAppendBuf(site_prefix, Line, 0);
 639         }
 640 }
 641
 642 void Header_HandleXFFHost(StrBuf *Line, ParsedHttpHdrs *hdr)
 643 {
 644         if ( (follow_xff) && (site_prefix == NULL)) {
 645                 site_prefix = NewStrBuf();
 646                 StrBufAppendPrintf(site_prefix, "http://");     /* this is naive; do something about it */
 647                 StrBufAppendBuf(site_prefix, Line, 0);
 648         }
 649 }
 650
 651
 652 void Header_HandleXFF(StrBuf *Line, ParsedHttpHdrs *hdr)
 653 {
 654         hdr->HR.browser_host = Line;
 655
 656         while (StrBufNum_tokens(hdr->HR.browser_host, ',') > 1) {
 657                 StrBufRemove_token(hdr->HR.browser_host, 0, ',');
 658         }
 659         StrBufTrim(hdr->HR.browser_host);
 660 }
 661
 662 void Header_HandleIfModSince(StrBuf *Line, ParsedHttpHdrs *hdr)
 663 {
 664         hdr->HR.if_modified_since = httpdate_to_timestamp(Line);
 665 }
 666
 667 void Header_HandleAcceptEncoding(StrBuf *Line, ParsedHttpHdrs *hdr)
 668 {
 669         /*
 670          * Can we compress?
 671          */
 672         if (strstr(&ChrPtr(Line)[16], "gzip")) {
 673                 hdr->HR.gzip_ok = 1;
 674         }
 675 }
 676 const char *ReqStrs[eNONE] = {
 677         "GET",
 678         "POST",
 679         "OPTIONS",
 680         "PROPFIND",
 681         "PUT",
 682         "DELETE",
 683         "HEAD",
 684         "MOVE",
 685         "COPY"
 686 };
 687
 688 void
 689 ServerStartModule_CONTEXT
 690 (void)
 691 {
 692         long *v;
 693         HttpReqTypes = NewHash(1, NULL);
 694         HttpHeaderHandler = NewHash(1, NULL);
 695
 696         v = malloc(sizeof(long));
 697         *v = eGET;
 698         Put(HttpReqTypes, HKEY("GET"), v, NULL);
 699
 700         v = malloc(sizeof(long));
 701         *v = ePOST;
 702         Put(HttpReqTypes, HKEY("POST"), v, NULL);
 703
 704         v = malloc(sizeof(long));
 705         *v = eOPTIONS;
 706         Put(HttpReqTypes, HKEY("OPTIONS"), v, NULL);
 707
 708         v = malloc(sizeof(long));
 709         *v = ePROPFIND;
 710         Put(HttpReqTypes, HKEY("PROPFIND"), v, NULL);
 711
 712         v = malloc(sizeof(long));
 713         *v = ePUT;
 714         Put(HttpReqTypes, HKEY("PUT"), v, NULL);
 715
 716         v = malloc(sizeof(long));
 717         *v = eDELETE;
 718         Put(HttpReqTypes, HKEY("DELETE"), v, NULL);
 719
 720         v = malloc(sizeof(long));
 721         *v = eHEAD;
 722         Put(HttpReqTypes, HKEY("HEAD"), v, NULL);
 723
 724         v = malloc(sizeof(long));
 725         *v = eMOVE;
 726         Put(HttpReqTypes, HKEY("MOVE"), v, NULL);
 727
 728         v = malloc(sizeof(long));
 729         *v = eCOPY;
 730         Put(HttpReqTypes, HKEY("COPY"), v, NULL);
 731 }
 732
 733 void
 734 ServerShutdownModule_CONTEXT
 735 (void)
 736 {
 737         DeleteHash(&HttpReqTypes);
 738         DeleteHash(&HttpHeaderHandler);
 739 }
 740
 741 void RegisterHeaderHandler(const char *Name, long Len, Header_Evaluator F)
 742 {
 743         OneHttpHeader *pHdr;
 744         pHdr = (OneHttpHeader*) malloc(sizeof(OneHttpHeader));
 745         memset(pHdr, 0, sizeof(OneHttpHeader));
 746         pHdr->H = F;
 747         Put(HttpHeaderHandler, Name, Len, pHdr, DestroyHttpHeaderHandler);
 748 }
 749
 750
 751 void
 752 InitModule_CONTEXT
 753 (void)
 754 {
 755         RegisterHeaderHandler(HKEY("CONTENT-LENGTH"), Header_HandleContentLength);
 756         RegisterHeaderHandler(HKEY("CONTENT-TYPE"), Header_HandleContentType);
 757         RegisterHeaderHandler(HKEY("X-FORWARDED-HOST"), Header_HandleXFFHost); /* Apache way... */
 758         RegisterHeaderHandler(HKEY("X-REAL-IP"), Header_HandleXFFHost);        /* NGinX way... */
 759         RegisterHeaderHandler(HKEY("HOST"), Header_HandleHost);
 760         RegisterHeaderHandler(HKEY("X-FORWARDED-FOR"), Header_HandleXFF);
 761         RegisterHeaderHandler(HKEY("ACCEPT-ENCODING"), Header_HandleAcceptEncoding);
 762         RegisterHeaderHandler(HKEY("IF-MODIFIED-SINCE"), Header_HandleIfModSince);
 763
 764         RegisterNamespace("CURRENT_USER", 0, 1, tmplput_current_user, NULL, CTX_NONE);
 765         RegisterNamespace("NONCE", 0, 0, tmplput_nonce, NULL, 0);
 766
 767         WebcitAddUrlHandler(HKEY("404"), "", 0, do_404, ANONYMOUS|COOKIEUNNEEDED);
 768 /*
 769  * Look for commonly-found probes of malware such as worms, viruses, trojans, and Microsoft Office.
 770  * Short-circuit these requests so we don't have to send them through the full processing loop.
 771  */
 772         WebcitAddUrlHandler(HKEY("scripts"), "", 0, do_404, ANONYMOUS|BOGUS);           /* /root.exe - Worms and trojans and viruses, oh my! */
 773         WebcitAddUrlHandler(HKEY("c"), "", 0, do_404, ANONYMOUS|BOGUS);         /* /winnt */
 774         WebcitAddUrlHandler(HKEY("MSADC"), "", 0, do_404, ANONYMOUS|BOGUS);
 775         WebcitAddUrlHandler(HKEY("_vti"), "", 0, do_404, ANONYMOUS|BOGUS);              /* Broken Microsoft DAV implementation */
 776         WebcitAddUrlHandler(HKEY("MSOffice"), "", 0, do_404, ANONYMOUS|BOGUS);          /* Stoopid MSOffice thinks everyone is IIS */
 777         WebcitAddUrlHandler(HKEY("nonexistenshit"), "", 0, do_404, ANONYMOUS|BOGUS);    /* Exploit found in the wild January 2009 */
 778 }
 779
 780
 781 void
 782 HttpNewModule_CONTEXT
 783 (ParsedHttpHdrs *httpreq)
 784 {
 785         httpreq->PlainArgs = NewStrBufPlain(NULL, SIZ);
 786         httpreq->this_page = NewStrBufPlain(NULL, SIZ);
 787 }
 788
 789 void
 790 HttpDetachModule_CONTEXT
 791 (ParsedHttpHdrs *httpreq)
 792 {
 793         FlushStrBuf(httpreq->PlainArgs);
 794         FlushStrBuf(httpreq->this_page);
 795         FlushStrBuf(httpreq->PlainArgs);
 796         DeleteHash(&httpreq->HTTPHeaders);
 797         memset(&httpreq->HR, 0, sizeof(HdrRefs));
 798 }
 799
 800 void
 801 HttpDestroyModule_CONTEXT
 802 (ParsedHttpHdrs *httpreq)
 803 {
 804         FreeStrBuf(&httpreq->this_page);
 805         FreeStrBuf(&httpreq->PlainArgs);
 806         FreeStrBuf(&httpreq->this_page);
 807         FreeStrBuf(&httpreq->PlainArgs);
 808         DeleteHash(&httpreq->HTTPHeaders);
 809
 810 }