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                         /* Any unbound session is a candidate */
 192                         if (sptr->wc_session == 0) {
 193                                 /* FIXME -- look for a session that is not only a candidate, but is
 194                                  * also NOT CURRENTLY LOCKED.  This will cause the proper size pool
 195                                  * to be created.
 196                                  */
 197                                 syslog(LOG_DEBUG, "\033[32mREUSING A SESSION\033[0m");
 198                                 TheSession = sptr;
 199                         }
 200                         break;
 201                 }
 202         }
 203         CtdlLogResult(pthread_mutex_unlock(ListMutex));
 204         if (TheSession == NULL)
 205                 syslog(1, "didn't find sessionkey [%d] for user [%s]\n",
 206                         Hdr->HR.SessionKey, ChrPtr(Hdr->c_username));
 207         return TheSession;
 208 }
 209
 210 wcsession *CreateSession(int Lockable, int Static, wcsession **wclist, ParsedHttpHdrs *Hdr, pthread_mutex_t *ListMutex)
 211 {
 212         wcsession *TheSession;
 213         TheSession = (wcsession *) malloc(sizeof(wcsession));
 214         memset(TheSession, 0, sizeof(wcsession));
 215         TheSession->Hdr = Hdr;
 216         TheSession->SessionKey = Hdr->HR.SessionKey;
 217         TheSession->serv_sock = (-1);
 218
 219         pthread_setspecific(MyConKey, (void *)TheSession);
 220
 221         /* If we're recreating a session that expired, it's best to give it the same
 222          * session number that it had before.  The client browser ought to pick up
 223          * the new session number and start using it, but in some rare situations it
 224          * doesn't, and that's a Bad Thing because it causes lots of spurious sessions
 225          * to get created.
 226          */
 227         if (Hdr->HR.desired_session == 0) {
 228                 TheSession->wc_session = GenerateSessionID();
 229                 syslog(3, "Created new session %d", TheSession->wc_session);
 230         }
 231         else {
 232                 TheSession->wc_session = Hdr->HR.desired_session;
 233                 syslog(3, "Re-created session %d", TheSession->wc_session);
 234         }
 235         Hdr->HR.Static = Static;
 236         session_new_modules(TheSession);
 237
 238         if (Lockable) {
 239                 pthread_mutex_init(&TheSession->SessionMutex, NULL);
 240
 241                 if (ListMutex != NULL)
 242                         CtdlLogResult(pthread_mutex_lock(ListMutex));
 243
 244                 if (wclist != NULL) {
 245                         TheSession->nonce = rand();
 246                         TheSession->next = *wclist;
 247                         *wclist = TheSession;
 248                 }
 249                 if (ListMutex != NULL)
 250                         CtdlLogResult(pthread_mutex_unlock(ListMutex));
 251         }
 252         return TheSession;
 253 }
 254
 255
 256 /* If it's a "force 404" situation then display the error and bail. */
 257 void do_404(void)
 258 {
 259         hprintf("HTTP/1.1 404 Not found\r\n");
 260         hprintf("Content-Type: text/plain\r\n");
 261         wc_printf("Not found\r\n");
 262         end_burst();
 263 }
 264
 265 int ReadHttpSubject(ParsedHttpHdrs *Hdr, StrBuf *Line, StrBuf *Buf)
 266 {
 267         const char *Args;
 268         void *vLine, *vHandler;
 269         const char *Pos = NULL;
 270
 271
 272         Hdr->HR.ReqLine = Line;
 273         /* The requesttype... GET, POST... */
 274         StrBufExtract_token(Buf, Hdr->HR.ReqLine, 0, ' ');
 275         if (GetHash(HttpReqTypes, SKEY(Buf), &vLine) &&
 276             (vLine != NULL))
 277         {
 278                 Hdr->HR.eReqType = *(long*)vLine;
 279         }
 280         else {
 281                 Hdr->HR.eReqType = eGET;
 282                 return 1;
 283         }
 284         StrBufCutLeft(Hdr->HR.ReqLine, StrLength(Buf) + 1);
 285
 286         /* the HTTP Version... */
 287         StrBufExtract_token(Buf, Hdr->HR.ReqLine, 1, ' ');
 288         StrBufCutRight(Hdr->HR.ReqLine, StrLength(Buf) + 1);
 289
 290         if (StrLength(Buf) == 0) {
 291                 Hdr->HR.eReqType = eGET;
 292                 return 1;
 293         }
 294
 295         StrBufAppendBuf(Hdr->this_page, Hdr->HR.ReqLine, 0);
 296
 297         /* chop Filename / query arguments */
 298         Args = strchr(ChrPtr(Hdr->HR.ReqLine), '?');
 299         if (Args == NULL) /* whe're not that picky about params... TODO: this will spoil '&' in filenames.*/
 300                 Args = strchr(ChrPtr(Hdr->HR.ReqLine), '&');
 301         if (Args != NULL) {
 302                 Args ++; /* skip the ? */
 303                 StrBufPlain(Hdr->PlainArgs,
 304                             Args,
 305                             StrLength(Hdr->HR.ReqLine) -
 306                             (Args - ChrPtr(Hdr->HR.ReqLine)));
 307                 StrBufCutAt(Hdr->HR.ReqLine, 0, Args - 1);
 308         } /* don't parse them yet, maybe we don't even care... */
 309
 310         /* now lookup what we are going to do with this... */
 311         /* skip first slash */
 312         StrBufExtract_NextToken(Buf, Hdr->HR.ReqLine, &Pos, '/');
 313         do {
 314                 StrBufExtract_NextToken(Buf, Hdr->HR.ReqLine, &Pos, '/');
 315
 316                 GetHash(HandlerHash, SKEY(Buf), &vHandler),
 317                 Hdr->HR.Handler = (WebcitHandler*) vHandler;
 318                 if (Hdr->HR.Handler == NULL)
 319                         break;
 320                 /*
 321                  * If the request is prefixed by "/webcit" then chop that off.  This
 322                  * allows a front end web server to forward all /webcit requests to us
 323                  * while still using the same web server port for other things.
 324                  */
 325                 if ((Hdr->HR.Handler->Flags & URLNAMESPACE) != 0)
 326                         continue;
 327                 break;
 328         } while (1);
 329         /* remove the handlername from the URL */
 330         if ((Pos != NULL) && (Pos != StrBufNOTNULL)){
 331                 StrBufCutLeft(Hdr->HR.ReqLine,
 332                               Pos - ChrPtr(Hdr->HR.ReqLine));
 333         }
 334
 335         if (Hdr->HR.Handler != NULL) {
 336                 if ((Hdr->HR.Handler->Flags & BOGUS) != 0)
 337                         return 1;
 338                 Hdr->HR.DontNeedAuth = (
 339                         ((Hdr->HR.Handler->Flags & ISSTATIC) != 0) ||
 340                         ((Hdr->HR.Handler->Flags & ANONYMOUS) != 0)
 341                         );
 342         }
 343         else {
 344                 Hdr->HR.DontNeedAuth = 1; /* Flat request? show him the login screen... */
 345         }
 346
 347         return 0;
 348 }
 349
 350 int AnalyseHeaders(ParsedHttpHdrs *Hdr)
 351 {
 352         OneHttpHeader *pHdr;
 353         void *vHdr;
 354         long HKLen;
 355         const char *HashKey;
 356         HashPos *at = GetNewHashPos(Hdr->HTTPHeaders, 0);
 357
 358         while (GetNextHashPos(Hdr->HTTPHeaders, at, &HKLen, &HashKey, &vHdr) &&
 359                (vHdr != NULL)) {
 360                 pHdr = (OneHttpHeader *)vHdr;
 361                 if (pHdr->HaveEvaluator)
 362                         pHdr->H(pHdr->Val, Hdr);
 363
 364         }
 365         DeleteHashPos(&at);
 366         return 0;
 367 }
 368
 369 /*const char *nix(void *vptr) {return ChrPtr( (StrBuf*)vptr);}*/
 370
 371 /*
 372  * Read in the request
 373  */
 374 int ReadHTTPRequest (ParsedHttpHdrs *Hdr)
 375 {
 376         const char *pch, *pchs, *pche;
 377         OneHttpHeader *pHdr;
 378         StrBuf *Line, *LastLine, *HeaderName;
 379         int nLine = 0;
 380         void *vF;
 381         int isbogus = 0;
 382
 383         HeaderName = NewStrBuf();
 384         LastLine = NULL;
 385         do {
 386                 nLine ++;
 387                 Line = NewStrBufPlain(NULL, SIZ / 4);
 388
 389                 if (ClientGetLine(Hdr, Line) < 0) return 1;
 390
 391                 if (StrLength(Line) == 0) {
 392                         FreeStrBuf(&Line);
 393                         continue;
 394                 }
 395                 if (nLine == 1) {
 396                         Hdr->HTTPHeaders = NewHash(1, NULL);
 397                         pHdr = (OneHttpHeader*) malloc(sizeof(OneHttpHeader));
 398                         memset(pHdr, 0, sizeof(OneHttpHeader));
 399                         pHdr->Val = Line;
 400                         Put(Hdr->HTTPHeaders, HKEY("GET /"), pHdr, DestroyHttpHeaderHandler);
 401                         syslog(9, "%s\n", ChrPtr(Line));
 402                         isbogus = ReadHttpSubject(Hdr, Line, HeaderName);
 403                         if (isbogus) break;
 404                         continue;
 405                 }
 406
 407                 /* Do we need to Unfold? */
 408                 if ((LastLine != NULL) &&
 409                     (isspace(*ChrPtr(Line)))) {
 410                         pch = pchs = ChrPtr(Line);
 411                         pche = pchs + StrLength(Line);
 412                         while (isspace(*pch) && (pch < pche))
 413                                 pch ++;
 414                         StrBufCutLeft(Line, pch - pchs);
 415                         StrBufAppendBuf(LastLine, Line, 0);
 416
 417                         FreeStrBuf(&Line);
 418                         continue;
 419                 }
 420
 421                 StrBufSanitizeAscii(Line, '§');
 422                 StrBufExtract_token(HeaderName, Line, 0, ':');
 423
 424                 pchs = ChrPtr(Line);
 425                 pche = pchs + StrLength(Line);
 426                 pch = pchs + StrLength(HeaderName) + 1;
 427                 pche = pchs + StrLength(Line);
 428                 while ((pch < pche) && isspace(*pch))
 429                         pch ++;
 430                 StrBufCutLeft(Line, pch - pchs);
 431
 432                 StrBufUpCase(HeaderName);
 433
 434                 pHdr = (OneHttpHeader*) malloc(sizeof(OneHttpHeader));
 435                 memset(pHdr, 0, sizeof(OneHttpHeader));
 436                 pHdr->Val = Line;
 437
 438                 if (GetHash(HttpHeaderHandler, SKEY(HeaderName), &vF) &&
 439                     (vF != NULL))
 440                 {
 441                         OneHttpHeader *FHdr = (OneHttpHeader*) vF;
 442                         pHdr->H = FHdr->H;
 443                         pHdr->HaveEvaluator = 1;
 444                 }
 445                 Put(Hdr->HTTPHeaders, SKEY(HeaderName), pHdr, DestroyHttpHeaderHandler);
 446                 LastLine = Line;
 447         } while (Line != NULL);
 448
 449         FreeStrBuf(&HeaderName);
 450
 451         return isbogus;
 452 }
 453
 454 void OverrideRequest(ParsedHttpHdrs *Hdr, const char *Line, long len)
 455 {
 456         StrBuf *Buf = NewStrBuf();
 457
 458         if (Hdr->HR.ReqLine != NULL) {
 459                 FlushStrBuf(Hdr->HR.ReqLine);
 460                 StrBufPlain(Hdr->HR.ReqLine, Line, len);
 461         }
 462         else {
 463                 Hdr->HR.ReqLine = NewStrBufPlain(Line, len);
 464         }
 465         ReadHttpSubject(Hdr, Hdr->HR.ReqLine, Buf);
 466
 467         FreeStrBuf(&Buf);
 468 }
 469
 470 /*
 471  * handle one request
 472  *
 473  * This loop gets called once for every HTTP connection made to WebCit.  At
 474  * this entry point we have an HTTP socket with a browser allegedly on the
 475  * other end, but we have not yet bound to a WebCit session.
 476  *
 477  * The job of this function is to locate the correct session and bind to it,
 478  * or create a session if necessary and bind to it, then run the WebCit
 479  * transaction loop.  Afterwards, we unbind from the session.  When this
 480  * function returns, the worker thread is then free to handle another
 481  * transaction.
 482  */
 483 void context_loop(ParsedHttpHdrs *Hdr)
 484 {
 485         int isbogus = 0;
 486         wcsession *TheSession;
 487         struct timeval tx_start;
 488         struct timeval tx_finish;
 489         int session_may_be_reused = 1;
 490
 491         gettimeofday(&tx_start, NULL);          /* start a stopwatch for performance timing */
 492
 493         /*
 494          * Find out what it is that the web browser is asking for
 495          */
 496         isbogus = ReadHTTPRequest(Hdr);
 497
 498         Hdr->HR.dav_depth = 32767; /* TODO: find a general way to have non-0 defaults */
 499         if (!isbogus)
 500                 isbogus = AnalyseHeaders(Hdr);
 501
 502         if ((isbogus) ||
 503             ((Hdr->HR.Handler != NULL) &&
 504              ((Hdr->HR.Handler->Flags & BOGUS) != 0)))
 505         {
 506                 wcsession *Bogus;
 507
 508                 Bogus = CreateSession(0, 1, NULL, Hdr, NULL);
 509
 510                 do_404();
 511
 512                 syslog(9, "HTTP: 404 [%ld.%06ld] %s %s \n",
 513                         ((tx_finish.tv_sec*1000000 + tx_finish.tv_usec) - (tx_start.tv_sec*1000000 + tx_start.tv_usec)) / 1000000,
 514                         ((tx_finish.tv_sec*1000000 + tx_finish.tv_usec) - (tx_start.tv_sec*1000000 + tx_start.tv_usec)) % 1000000,
 515                         ReqStrs[Hdr->HR.eReqType],
 516                         ChrPtr(Hdr->this_page)
 517                         );
 518                 session_detach_modules(Bogus);
 519                 session_destroy_modules(&Bogus);
 520                 return;
 521         }
 522
 523         if ((Hdr->HR.Handler != NULL) && ((Hdr->HR.Handler->Flags & ISSTATIC) != 0))
 524         {
 525                 wcsession *Static;
 526                 Static = CreateSession(0, 1, NULL, Hdr, NULL);
 527
 528                 Hdr->HR.Handler->F();
 529
 530                 /* How long did this transaction take? */
 531                 gettimeofday(&tx_finish, NULL);
 532
 533                 syslog(9, "HTTP: 200 [%ld.%06ld] %s %s \n",
 534                         ((tx_finish.tv_sec*1000000 + tx_finish.tv_usec) - (tx_start.tv_sec*1000000 + tx_start.tv_usec)) / 1000000,
 535                         ((tx_finish.tv_sec*1000000 + tx_finish.tv_usec) - (tx_start.tv_sec*1000000 + tx_start.tv_usec)) % 1000000,
 536                         ReqStrs[Hdr->HR.eReqType],
 537                         ChrPtr(Hdr->this_page)
 538                 );
 539                 session_detach_modules(Static);
 540                 session_destroy_modules(&Static);
 541                 return;
 542         }
 543
 544         if (Hdr->HR.got_auth == AUTH_BASIC) {
 545                 CheckAuthBasic(Hdr);
 546         }
 547
 548         if (Hdr->HR.got_auth) {
 549                 session_may_be_reused = 0;
 550         }
 551
 552         /*
 553          * See if there's an existing session open with the desired ID or user/pass
 554          */
 555         TheSession = FindSession(&SessionList, Hdr, &SessionListMutex);
 556
 557         /*
 558          * Create a new session if we have to
 559          */
 560         if (TheSession == NULL) {
 561                 TheSession = CreateSession(1, 0, &SessionList, Hdr, &SessionListMutex);
 562
 563                 if (    (StrLength(Hdr->c_username) == 0)
 564                         && (!Hdr->HR.DontNeedAuth)
 565                         && (Hdr->HR.Handler != NULL)
 566                         && ((XHTTP_COMMANDS & Hdr->HR.Handler->Flags) == XHTTP_COMMANDS)
 567                 ) {
 568                         OverrideRequest(Hdr, HKEY("GET /401 HTTP/1.0"));
 569                         Hdr->HR.prohibit_caching = 1;
 570                 }
 571
 572                 if (StrLength(Hdr->c_language) > 0) {
 573                         syslog(9, "Session cookie requests language '%s'\n", ChrPtr(Hdr->c_language));
 574                         set_selected_language(ChrPtr(Hdr->c_language));
 575                         go_selected_language();
 576                 }
 577         }
 578
 579         /*
 580          * A future improvement might be to check the session integrity
 581          * at this point before continuing.
 582          */
 583
 584         /*
 585          * Bind to the session and perform the transaction
 586          */
 587         if (pthread_mutex_lock(&TheSession->SessionMutex)) {
 588                 syslog(LOG_DEBUG, "\033[31mWAITING FOR SESSION LOCK\033[0m");
 589                 CtdlLogResult(pthread_mutex_lock(&TheSession->SessionMutex));
 590         }
 591
 592         pthread_setspecific(MyConKey, (void *)TheSession);
 593
 594         TheSession->lastreq = time(NULL);                       /* log */
 595         TheSession->Hdr = Hdr;
 596
 597         session_attach_modules(TheSession);
 598         session_loop();                         /* do transaction */
 599
 600
 601         /* How long did this transaction take? */
 602         gettimeofday(&tx_finish, NULL);
 603
 604
 605         syslog(9, "HTTP: 200 [%ld.%06ld] %s %s \n",
 606                 ((tx_finish.tv_sec*1000000 + tx_finish.tv_usec) - (tx_start.tv_sec*1000000 + tx_start.tv_usec)) / 1000000,
 607                 ((tx_finish.tv_sec*1000000 + tx_finish.tv_usec) - (tx_start.tv_sec*1000000 + tx_start.tv_usec)) % 1000000,
 608                 ReqStrs[Hdr->HR.eReqType],
 609                 ChrPtr(Hdr->this_page)
 610         );
 611
 612         session_detach_modules(TheSession);
 613
 614         /* If *this* very transaction did not explicitly specify a session cookie,
 615          * and it did not log in, we want to flag the session as a candidate for
 616          * re-use by the next unbound client that comes along.  This keeps our session
 617          * table from getting bombarded with new sessions when, for example, a web
 618          * spider crawls the site without using cookies.
 619          */
 620         if ((session_may_be_reused) && (!WC->logged_in)) {
 621                 WC->wc_session = 0;
 622         }
 623
 624         TheSession->Hdr = NULL;
 625         CtdlLogResult(pthread_mutex_unlock(&TheSession->SessionMutex));
 626 }
 627
 628 void tmplput_nonce(StrBuf *Target, WCTemplputParams *TP)
 629 {
 630         wcsession *WCC = WC;
 631         StrBufAppendPrintf(Target, "%ld",
 632                            (WCC != NULL)? WCC->nonce:0);
 633 }
 634
 635 void tmplput_current_user(StrBuf *Target, WCTemplputParams *TP)
 636 {
 637         StrBufAppendTemplate(Target, TP, WC->wc_fullname, 0);
 638 }
 639
 640 void Header_HandleContentLength(StrBuf *Line, ParsedHttpHdrs *hdr)
 641 {
 642         hdr->HR.ContentLength = StrToi(Line);
 643 }
 644
 645 void Header_HandleContentType(StrBuf *Line, ParsedHttpHdrs *hdr)
 646 {
 647         hdr->HR.ContentType = Line;
 648 }
 649
 650
 651 void Header_HandleHost(StrBuf *Line, ParsedHttpHdrs *hdr)
 652 {
 653         if (hdr->HostHeader != NULL) {
 654                 FreeStrBuf(&hdr->HostHeader);
 655         }
 656         hdr->HostHeader = NewStrBuf();
 657         StrBufAppendPrintf(hdr->HostHeader, "%s://", (is_https ? "https" : "http") );
 658         StrBufAppendBuf(hdr->HostHeader, Line, 0);
 659 }
 660
 661 void Header_HandleXFFHost(StrBuf *Line, ParsedHttpHdrs *hdr)
 662 {
 663         if (!follow_xff) return;
 664
 665         if (hdr->HostHeader != NULL) {
 666                 FreeStrBuf(&hdr->HostHeader);
 667         }
 668
 669         hdr->HostHeader = NewStrBuf();
 670         StrBufAppendPrintf(hdr->HostHeader, "http://"); /* this is naive; do something about it */
 671         StrBufAppendBuf(hdr->HostHeader, Line, 0);
 672 }
 673
 674
 675 void Header_HandleXFF(StrBuf *Line, ParsedHttpHdrs *hdr)
 676 {
 677         hdr->HR.browser_host = Line;
 678
 679         while (StrBufNum_tokens(hdr->HR.browser_host, ',') > 1) {
 680                 StrBufRemove_token(hdr->HR.browser_host, 0, ',');
 681         }
 682         StrBufTrim(hdr->HR.browser_host);
 683 }
 684
 685 void Header_HandleIfModSince(StrBuf *Line, ParsedHttpHdrs *hdr)
 686 {
 687         hdr->HR.if_modified_since = httpdate_to_timestamp(Line);
 688 }
 689
 690 void Header_HandleAcceptEncoding(StrBuf *Line, ParsedHttpHdrs *hdr)
 691 {
 692         /*
 693          * Can we compress?
 694          */
 695         if (strstr(&ChrPtr(Line)[16], "gzip")) {
 696                 hdr->HR.gzip_ok = 1;
 697         }
 698 }
 699 const char *ReqStrs[eNONE] = {
 700         "GET",
 701         "POST",
 702         "OPTIONS",
 703         "PROPFIND",
 704         "PUT",
 705         "DELETE",
 706         "HEAD",
 707         "MOVE",
 708         "COPY"
 709 };
 710
 711 void
 712 ServerStartModule_CONTEXT
 713 (void)
 714 {
 715         long *v;
 716         HttpReqTypes = NewHash(1, NULL);
 717         HttpHeaderHandler = NewHash(1, NULL);
 718
 719         v = malloc(sizeof(long));
 720         *v = eGET;
 721         Put(HttpReqTypes, HKEY("GET"), v, NULL);
 722
 723         v = malloc(sizeof(long));
 724         *v = ePOST;
 725         Put(HttpReqTypes, HKEY("POST"), v, NULL);
 726
 727         v = malloc(sizeof(long));
 728         *v = eOPTIONS;
 729         Put(HttpReqTypes, HKEY("OPTIONS"), v, NULL);
 730
 731         v = malloc(sizeof(long));
 732         *v = ePROPFIND;
 733         Put(HttpReqTypes, HKEY("PROPFIND"), v, NULL);
 734
 735         v = malloc(sizeof(long));
 736         *v = ePUT;
 737         Put(HttpReqTypes, HKEY("PUT"), v, NULL);
 738
 739         v = malloc(sizeof(long));
 740         *v = eDELETE;
 741         Put(HttpReqTypes, HKEY("DELETE"), v, NULL);
 742
 743         v = malloc(sizeof(long));
 744         *v = eHEAD;
 745         Put(HttpReqTypes, HKEY("HEAD"), v, NULL);
 746
 747         v = malloc(sizeof(long));
 748         *v = eMOVE;
 749         Put(HttpReqTypes, HKEY("MOVE"), v, NULL);
 750
 751         v = malloc(sizeof(long));
 752         *v = eCOPY;
 753         Put(HttpReqTypes, HKEY("COPY"), v, NULL);
 754 }
 755
 756 void
 757 ServerShutdownModule_CONTEXT
 758 (void)
 759 {
 760         DeleteHash(&HttpReqTypes);
 761         DeleteHash(&HttpHeaderHandler);
 762 }
 763
 764 void RegisterHeaderHandler(const char *Name, long Len, Header_Evaluator F)
 765 {
 766         OneHttpHeader *pHdr;
 767         pHdr = (OneHttpHeader*) malloc(sizeof(OneHttpHeader));
 768         memset(pHdr, 0, sizeof(OneHttpHeader));
 769         pHdr->H = F;
 770         Put(HttpHeaderHandler, Name, Len, pHdr, DestroyHttpHeaderHandler);
 771 }
 772
 773
 774 void
 775 InitModule_CONTEXT
 776 (void)
 777 {
 778         RegisterHeaderHandler(HKEY("CONTENT-LENGTH"), Header_HandleContentLength);
 779         RegisterHeaderHandler(HKEY("CONTENT-TYPE"), Header_HandleContentType);
 780         RegisterHeaderHandler(HKEY("X-FORWARDED-HOST"), Header_HandleXFFHost); /* Apache way... */
 781         RegisterHeaderHandler(HKEY("X-REAL-IP"), Header_HandleXFFHost);        /* NGinX way... */
 782         RegisterHeaderHandler(HKEY("HOST"), Header_HandleHost);
 783         RegisterHeaderHandler(HKEY("X-FORWARDED-FOR"), Header_HandleXFF);
 784         RegisterHeaderHandler(HKEY("ACCEPT-ENCODING"), Header_HandleAcceptEncoding);
 785         RegisterHeaderHandler(HKEY("IF-MODIFIED-SINCE"), Header_HandleIfModSince);
 786
 787         RegisterNamespace("CURRENT_USER", 0, 1, tmplput_current_user, NULL, CTX_NONE);
 788         RegisterNamespace("NONCE", 0, 0, tmplput_nonce, NULL, 0);
 789
 790         WebcitAddUrlHandler(HKEY("404"), "", 0, do_404, ANONYMOUS|COOKIEUNNEEDED);
 791 /*
 792  * Look for commonly-found probes of malware such as worms, viruses, trojans, and Microsoft Office.
 793  * Short-circuit these requests so we don't have to send them through the full processing loop.
 794  */
 795         WebcitAddUrlHandler(HKEY("scripts"), "", 0, do_404, ANONYMOUS|BOGUS);           /* /root.exe - Worms and trojans and viruses, oh my! */
 796         WebcitAddUrlHandler(HKEY("c"), "", 0, do_404, ANONYMOUS|BOGUS);         /* /winnt */
 797         WebcitAddUrlHandler(HKEY("MSADC"), "", 0, do_404, ANONYMOUS|BOGUS);
 798         WebcitAddUrlHandler(HKEY("_vti"), "", 0, do_404, ANONYMOUS|BOGUS);              /* Broken Microsoft DAV implementation */
 799         WebcitAddUrlHandler(HKEY("MSOffice"), "", 0, do_404, ANONYMOUS|BOGUS);          /* Stoopid MSOffice thinks everyone is IIS */
 800         WebcitAddUrlHandler(HKEY("nonexistenshit"), "", 0, do_404, ANONYMOUS|BOGUS);    /* Exploit found in the wild January 2009 */
 801 }
 802
 803
 804 void
 805 HttpNewModule_CONTEXT
 806 (ParsedHttpHdrs *httpreq)
 807 {
 808         httpreq->PlainArgs = NewStrBufPlain(NULL, SIZ);
 809         httpreq->this_page = NewStrBufPlain(NULL, SIZ);
 810 }
 811
 812 void
 813 HttpDetachModule_CONTEXT
 814 (ParsedHttpHdrs *httpreq)
 815 {
 816         FlushStrBuf(httpreq->PlainArgs);
 817         FlushStrBuf(httpreq->HostHeader);
 818         FlushStrBuf(httpreq->this_page);
 819         FlushStrBuf(httpreq->PlainArgs);
 820         DeleteHash(&httpreq->HTTPHeaders);
 821         memset(&httpreq->HR, 0, sizeof(HdrRefs));
 822 }
 823
 824 void
 825 HttpDestroyModule_CONTEXT
 826 (ParsedHttpHdrs *httpreq)
 827 {
 828         FreeStrBuf(&httpreq->this_page);
 829         FreeStrBuf(&httpreq->PlainArgs);
 830         FreeStrBuf(&httpreq->this_page);
 831         FreeStrBuf(&httpreq->PlainArgs);
 832         FreeStrBuf(&httpreq->HostHeader);
 833         DeleteHash(&httpreq->HTTPHeaders);
 834
 835 }