src/client_side_reply.cc

   1 /*
   2  * Copyright (C) 1996-2015 The Squid Software Foundation and contributors
   3  *
   4  * Squid software is distributed under GPLv2+ license and includes
   5  * contributions from numerous individuals and organizations.
   6  * Please see the COPYING and CONTRIBUTORS files for details.
   7  */
   8
   9 /* DEBUG: section 88    Client-side Reply Routines */
  10
  11 #include "squid.h"
  12 #include "acl/FilledChecklist.h"
  13 #include "acl/Gadgets.h"
  14 #include "anyp/PortCfg.h"
  15 #include "client_side_reply.h"
  16 #include "errorpage.h"
  17 #include "ETag.h"
  18 #include "fd.h"
  19 #include "fde.h"
  20 #include "format/Token.h"
  21 #include "FwdState.h"
  22 #include "globals.h"
  23 #include "globals.h"
  24 #include "HttpHeaderTools.h"
  25 #include "HttpReply.h"
  26 #include "HttpRequest.h"
  27 #include "ip/QosConfig.h"
  28 #include "ipcache.h"
  29 #include "log/access_log.h"
  30 #include "MemObject.h"
  31 #include "mime_header.h"
  32 #include "neighbors.h"
  33 #include "refresh.h"
  34 #include "RequestFlags.h"
  35 #include "SquidConfig.h"
  36 #include "SquidTime.h"
  37 #include "Store.h"
  38 #include "StrList.h"
  39 #include "tools.h"
  40 #include "URL.h"
  41 #if USE_AUTH
  42 #include "auth/UserRequest.h"
  43 #endif
  44 #if USE_DELAY_POOLS
  45 #include "DelayPools.h"
  46 #endif
  47 #if USE_SQUID_ESI
  48 #include "esi/Esi.h"
  49 #endif
  50
  51 #include <memory>
  52
  53 CBDATA_CLASS_INIT(clientReplyContext);
  54
  55 /* Local functions */
  56 extern "C" CSS clientReplyStatus;
  57 ErrorState *clientBuildError(err_type, Http::StatusCode, char const *, Ip::Address &, HttpRequest *);
  58
  59 /* privates */
  60
  61 clientReplyContext::~clientReplyContext()
  62 {
  63     deleting = true;
  64     /* This may trigger a callback back into SendMoreData as the cbdata
  65      * is still valid
  66      */
  67     removeClientStoreReference(&sc, http);
  68     /* old_entry might still be set if we didn't yet get the reply
  69      * code in HandleIMSReply() */
  70     removeStoreReference(&old_sc, &old_entry);
  71     safe_free(tempBuffer.data);
  72     cbdataReferenceDone(http);
  73     HTTPMSGUNLOCK(reply);
  74 }
  75
  76 clientReplyContext::clientReplyContext(ClientHttpRequest *clientContext) :
  77     purgeStatus(Http::scNone),
  78     lookingforstore(0),
  79     http(cbdataReference(clientContext)),
  80     headers_sz(0),
  81     sc(NULL),
  82     old_reqsize(0),
  83     reqsize(0),
  84     reqofs(0),
  85 #if USE_CACHE_DIGESTS
  86     lookup_type(NULL),
  87 #endif
  88     ourNode(NULL),
  89     reply(NULL),
  90     old_entry(NULL),
  91     old_sc(NULL),
  92     deleting(false)
  93 {
  94     *tempbuf = 0;
  95 }
  96
  97 /** Create an error in the store awaiting the client side to read it.
  98  *
  99  * This may be better placed in the clientStream logic, but it has not been
 100  * relocated there yet
 101  */
 102 void
 103 clientReplyContext::setReplyToError(
 104     err_type err, Http::StatusCode status, const HttpRequestMethod& method, char const *uri,
 105     Ip::Address &addr, HttpRequest * failedrequest, const char *unparsedrequest,
 106 #if USE_AUTH
 107     Auth::UserRequest::Pointer auth_user_request
 108 #else
 109     void*
 110 #endif
 111 )
 112 {
 113     ErrorState *errstate = clientBuildError(err, status, uri, addr, failedrequest);
 114
 115     if (unparsedrequest)
 116         errstate->request_hdrs = xstrdup(unparsedrequest);
 117
 118 #if USE_AUTH
 119     errstate->auth_user_request = auth_user_request;
 120 #endif
 121     setReplyToError(method, errstate);
 122 }
 123
 124 void clientReplyContext::setReplyToError(const HttpRequestMethod& method, ErrorState *errstate)
 125 {
 126     if (errstate->httpStatus == Http::scNotImplemented && http->request)
 127         /* prevent confusion over whether we default to persistent or not */
 128         http->request->flags.proxyKeepalive = false;
 129
 130     http->al->http.code = errstate->httpStatus;
 131
 132     if (http->request)
 133         http->request->ignoreRange("responding with a Squid-generated error");
 134
 135     createStoreEntry(method, RequestFlags());
 136     assert(errstate->callback_data == NULL);
 137     errorAppendEntry(http->storeEntry(), errstate);
 138     /* Now the caller reads to get this */
 139 }
 140
 141 void
 142 clientReplyContext::setReplyToReply(HttpReply *futureReply)
 143 {
 144     Must(futureReply);
 145     http->al->http.code = futureReply->sline.status();
 146
 147     HttpRequestMethod method;
 148     if (http->request) { // nil on responses to unparsable requests
 149         http->request->ignoreRange("responding with a Squid-generated reply");
 150         method = http->request->method;
 151     }
 152
 153     createStoreEntry(method, RequestFlags());
 154
 155     http->storeEntry()->storeErrorResponse(futureReply);
 156     /* Now the caller reads to get futureReply */
 157 }
 158
 159 // Assumes that the entry contains an error response without Content-Range.
 160 // To use with regular entries, make HTTP Range header removal conditional.
 161 void clientReplyContext::setReplyToStoreEntry(StoreEntry *entry, const char *reason)
 162 {
 163     entry->lock("clientReplyContext::setReplyToStoreEntry"); // removeClientStoreReference() unlocks
 164     sc = storeClientListAdd(entry, this);
 165 #if USE_DELAY_POOLS
 166     sc->setDelayId(DelayId::DelayClient(http));
 167 #endif
 168     reqofs = 0;
 169     reqsize = 0;
 170     if (http->request)
 171         http->request->ignoreRange(reason);
 172     flags.storelogiccomplete = 1;
 173     http->storeEntry(entry);
 174 }
 175
 176 void
 177 clientReplyContext::removeStoreReference(store_client ** scp,
 178         StoreEntry ** ep)
 179 {
 180     StoreEntry *e;
 181     store_client *sc_tmp = *scp;
 182
 183     if ((e = *ep) != NULL) {
 184         *ep = NULL;
 185         storeUnregister(sc_tmp, e, this);
 186         *scp = NULL;
 187         e->unlock("clientReplyContext::removeStoreReference");
 188     }
 189 }
 190
 191 void
 192 clientReplyContext::removeClientStoreReference(store_client **scp, ClientHttpRequest *aHttpRequest)
 193 {
 194     StoreEntry *reference = aHttpRequest->storeEntry();
 195     removeStoreReference(scp, &reference);
 196     aHttpRequest->storeEntry(reference);
 197 }
 198
 199 void
 200 clientReplyContext::saveState()
 201 {
 202     assert(old_sc == NULL);
 203     debugs(88, 3, "clientReplyContext::saveState: saving store context");
 204     old_entry = http->storeEntry();
 205     old_sc = sc;
 206     old_reqsize = reqsize;
 207     tempBuffer.offset = reqofs;
 208     /* Prevent accessing the now saved entries */
 209     http->storeEntry(NULL);
 210     sc = NULL;
 211     reqsize = 0;
 212     reqofs = 0;
 213 }
 214
 215 void
 216 clientReplyContext::restoreState()
 217 {
 218     assert(old_sc != NULL);
 219     debugs(88, 3, "clientReplyContext::restoreState: Restoring store context");
 220     removeClientStoreReference(&sc, http);
 221     http->storeEntry(old_entry);
 222     sc = old_sc;
 223     reqsize = old_reqsize;
 224     reqofs = tempBuffer.offset;
 225     /* Prevent accessed the old saved entries */
 226     old_entry = NULL;
 227     old_sc = NULL;
 228     old_reqsize = 0;
 229     tempBuffer.offset = 0;
 230 }
 231
 232 void
 233 clientReplyContext::startError(ErrorState * err)
 234 {
 235     createStoreEntry(http->request->method, RequestFlags());
 236     triggerInitialStoreRead();
 237     errorAppendEntry(http->storeEntry(), err);
 238 }
 239
 240 clientStreamNode *
 241 clientReplyContext::getNextNode() const
 242 {
 243     return (clientStreamNode *)ourNode->node.next->data;
 244 }
 245
 246 /* This function is wrong - the client parameters don't include the
 247  * header offset
 248  */
 249 void
 250 clientReplyContext::triggerInitialStoreRead()
 251 {
 252     /* when confident, 0 becomes reqofs, and then this factors into
 253      * startSendProcess
 254      */
 255     assert(reqofs == 0);
 256     StoreIOBuffer localTempBuffer (next()->readBuffer.length, 0, next()->readBuffer.data);
 257     storeClientCopy(sc, http->storeEntry(), localTempBuffer, SendMoreData, this);
 258 }
 259
 260 /* there is an expired entry in the store.
 261  * setup a temporary buffer area and perform an IMS to the origin
 262  */
 263 void
 264 clientReplyContext::processExpired()
 265 {
 266     const char *url = storeId();
 267     StoreEntry *entry = NULL;
 268     debugs(88, 3, "clientReplyContext::processExpired: '" << http->uri << "'");
 269     assert(http->storeEntry()->lastmod >= 0);
 270     /*
 271      * check if we are allowed to contact other servers
 272      * @?@: Instead of a 504 (Gateway Timeout) reply, we may want to return
 273      *      a stale entry *if* it matches client requirements
 274      */
 275
 276     if (http->onlyIfCached()) {
 277         processOnlyIfCachedMiss();
 278         return;
 279     }
 280
 281     http->request->flags.refresh = true;
 282 #if STORE_CLIENT_LIST_DEBUG
 283     /* Prevent a race with the store client memory free routines
 284      */
 285     assert(storeClientIsThisAClient(sc, this));
 286 #endif
 287     /* Prepare to make a new temporary request */
 288     saveState();
 289     entry = storeCreateEntry(url,
 290                              http->log_uri, http->request->flags, http->request->method);
 291     /* NOTE, don't call StoreEntry->lock(), storeCreateEntry() does it */
 292     sc = storeClientListAdd(entry, this);
 293 #if USE_DELAY_POOLS
 294     /* delay_id is already set on original store client */
 295     sc->setDelayId(DelayId::DelayClient(http));
 296 #endif
 297
 298     http->request->lastmod = old_entry->lastmod;
 299
 300     if (!http->request->header.has(Http::HdrType::IF_NONE_MATCH)) {
 301         ETag etag = {NULL, -1}; // TODO: make that a default ETag constructor
 302         if (old_entry->hasEtag(etag) && !etag.weak)
 303             http->request->etag = etag.str;
 304     }
 305
 306     debugs(88, 5, "clientReplyContext::processExpired : lastmod " << entry->lastmod );
 307     http->storeEntry(entry);
 308     assert(http->out.offset == 0);
 309     assert(http->request->clientConnectionManager == http->getConn());
 310
 311     /*
 312      * A refcounted pointer so that FwdState stays around as long as
 313      * this clientReplyContext does
 314      */
 315     Comm::ConnectionPointer conn = http->getConn() != NULL ? http->getConn()->clientConnection : NULL;
 316     FwdState::Start(conn, http->storeEntry(), http->request, http->al);
 317
 318     /* Register with storage manager to receive updates when data comes in. */
 319
 320     if (EBIT_TEST(entry->flags, ENTRY_ABORTED))
 321         debugs(88, DBG_CRITICAL, "clientReplyContext::processExpired: Found ENTRY_ABORTED object");
 322
 323     {
 324         /* start counting the length from 0 */
 325         StoreIOBuffer localTempBuffer(HTTP_REQBUF_SZ, 0, tempbuf);
 326         storeClientCopy(sc, entry, localTempBuffer, HandleIMSReply, this);
 327     }
 328 }
 329
 330 void
 331 clientReplyContext::sendClientUpstreamResponse()
 332 {
 333     StoreIOBuffer tempresult;
 334     removeStoreReference(&old_sc, &old_entry);
 335     /* here the data to send is the data we just received */
 336     tempBuffer.offset = 0;
 337     old_reqsize = 0;
 338     /* sendMoreData tracks the offset as well.
 339      * Force it back to zero */
 340     reqofs = 0;
 341     assert(!EBIT_TEST(http->storeEntry()->flags, ENTRY_ABORTED));
 342     /* TODO: provide sendMoreData with the ready parsed reply */
 343     tempresult.length = reqsize;
 344     tempresult.data = tempbuf;
 345     sendMoreData(tempresult);
 346 }
 347
 348 void
 349 clientReplyContext::HandleIMSReply(void *data, StoreIOBuffer result)
 350 {
 351     clientReplyContext *context = (clientReplyContext *)data;
 352     context->handleIMSReply(result);
 353 }
 354
 355 void
 356 clientReplyContext::sendClientOldEntry()
 357 {
 358     /* Get the old request back */
 359     restoreState();
 360     /* here the data to send is in the next nodes buffers already */
 361     assert(!EBIT_TEST(http->storeEntry()->flags, ENTRY_ABORTED));
 362     /* sendMoreData tracks the offset as well.
 363      * Force it back to zero */
 364     reqofs = 0;
 365     StoreIOBuffer tempresult (reqsize, reqofs, next()->readBuffer.data);
 366     sendMoreData(tempresult);
 367 }
 368
 369 /* This is the workhorse of the HandleIMSReply callback.
 370  *
 371  * It is called when we've got data back from the origin following our
 372  * IMS request to revalidate a stale entry.
 373  */
 374 void
 375 clientReplyContext::handleIMSReply(StoreIOBuffer result)
 376 {
 377     if (deleting)
 378         return;
 379
 380     debugs(88, 3, "handleIMSReply: " << http->storeEntry()->url() << ", " << (long unsigned) result.length << " bytes" );
 381
 382     if (http->storeEntry() == NULL)
 383         return;
 384
 385     if (result.flags.error && !EBIT_TEST(http->storeEntry()->flags, ENTRY_ABORTED))
 386         return;
 387
 388     /* update size of the request */
 389     reqsize = result.length + reqofs;
 390
 391     const Http::StatusCode status = http->storeEntry()->getReply()->sline.status();
 392
 393     // request to origin was aborted
 394     if (EBIT_TEST(http->storeEntry()->flags, ENTRY_ABORTED)) {
 395         debugs(88, 3, "handleIMSReply: request to origin aborted '" << http->storeEntry()->url() << "', sending old entry to client" );
 396         http->logType = LOG_TCP_REFRESH_FAIL_OLD;
 397         sendClientOldEntry();
 398     }
 399
 400     HttpReply *old_rep = (HttpReply *) old_entry->getReply();
 401
 402     // origin replied 304
 403     if (status == Http::scNotModified) {
 404         http->logType = LOG_TCP_REFRESH_UNMODIFIED;
 405         http->request->flags.staleIfHit = false; // old_entry is no longer stale
 406
 407         // update headers on existing entry
 408         old_rep->updateOnNotModified(http->storeEntry()->getReply());
 409         old_entry->timestampsSet();
 410
 411         // if client sent IMS
 412
 413         if (http->request->flags.ims && !old_entry->modifiedSince(http->request)) {
 414             // forward the 304 from origin
 415             debugs(88, 3, "handleIMSReply: origin replied 304, revalidating existing entry and forwarding 304 to client");
 416             sendClientUpstreamResponse();
 417         } else {
 418             // send existing entry, it's still valid
 419             debugs(88, 3, "handleIMSReply: origin replied 304, revalidating existing entry and sending " <<
 420                    old_rep->sline.status() << " to client");
 421             sendClientOldEntry();
 422         }
 423     }
 424
 425     // origin replied with a non-error code
 426     else if (status > Http::scNone && status < Http::scInternalServerError) {
 427         // forward response from origin
 428         http->logType = LOG_TCP_REFRESH_MODIFIED;
 429         debugs(88, 3, "handleIMSReply: origin replied " << status << ", replacing existing entry and forwarding to client");
 430         sendClientUpstreamResponse();
 431     }
 432
 433     // origin replied with an error
 434     else if (http->request->flags.failOnValidationError) {
 435         http->logType = LOG_TCP_REFRESH_FAIL_ERR;
 436         debugs(88, 3, "handleIMSReply: origin replied with error " << status <<
 437                ", forwarding to client due to fail_on_validation_err");
 438         sendClientUpstreamResponse();
 439     } else {
 440         // ignore and let client have old entry
 441         http->logType = LOG_TCP_REFRESH_FAIL_OLD;
 442         debugs(88, 3, "handleIMSReply: origin replied with error " <<
 443                status << ", sending old entry (" << old_rep->sline.status() << ") to client");
 444         sendClientOldEntry();
 445     }
 446 }
 447
 448 SQUIDCEXTERN CSR clientGetMoreData;
 449 SQUIDCEXTERN CSD clientReplyDetach;
 450
 451 /**
 452  * clientReplyContext::cacheHit Should only be called until the HTTP reply headers
 453  * have been parsed.  Normally this should be a single call, but
 454  * it might take more than one.  As soon as we have the headers,
 455  * we hand off to clientSendMoreData, processExpired, or
 456  * processMiss.
 457  */
 458 void
 459 clientReplyContext::CacheHit(void *data, StoreIOBuffer result)
 460 {
 461     clientReplyContext *context = (clientReplyContext *)data;
 462     context->cacheHit(result);
 463 }
 464
 465 /**
 466  * Process a possible cache HIT.
 467  */
 468 void
 469 clientReplyContext::cacheHit(StoreIOBuffer result)
 470 {
 471     /** Ignore if the HIT object is being deleted. */
 472     if (deleting) {
 473         debugs(88, 3, "HIT object being deleted. Ignore the HIT.");
 474         return;
 475     }
 476
 477     StoreEntry *e = http->storeEntry();
 478
 479     HttpRequest *r = http->request;
 480
 481     debugs(88, 3, "clientCacheHit: " << http->uri << ", " << result.length << " bytes");
 482
 483     if (http->storeEntry() == NULL) {
 484         debugs(88, 3, "clientCacheHit: request aborted");
 485         return;
 486     } else if (result.flags.error) {
 487         /* swap in failure */
 488         debugs(88, 3, "clientCacheHit: swapin failure for " << http->uri);
 489         http->logType = LOG_TCP_SWAPFAIL_MISS;
 490         removeClientStoreReference(&sc, http);
 491         processMiss();
 492         return;
 493     }
 494
 495     if (result.length == 0) {
 496         debugs(88, 5, "store IO buffer has no content. MISS");
 497         /* the store couldn't get enough data from the file for us to id the
 498          * object
 499          */
 500         /* treat as a miss */
 501         http->logType = LOG_TCP_MISS;
 502         processMiss();
 503         return;
 504     }
 505
 506     assert(!EBIT_TEST(e->flags, ENTRY_ABORTED));
 507     /* update size of the request */
 508     reqsize = result.length + reqofs;
 509
 510     /*
 511      * Got the headers, now grok them
 512      */
 513     assert(http->logType.oldType == LOG_TCP_HIT);
 514
 515     if (http->request->storeId().cmp(e->mem_obj->storeId()) != 0) {
 516         debugs(33, DBG_IMPORTANT, "clientProcessHit: URL mismatch, '" << e->mem_obj->storeId() << "' != '" << http->request->storeId() << "'");
 517         http->logType = LOG_TCP_MISS; // we lack a more precise LOG_*_MISS code
 518         processMiss();
 519         return;
 520     }
 521
 522     switch (varyEvaluateMatch(e, r)) {
 523
 524     case VARY_NONE:
 525         /* No variance detected. Continue as normal */
 526         break;
 527
 528     case VARY_MATCH:
 529         /* This is the correct entity for this request. Continue */
 530         debugs(88, 2, "clientProcessHit: Vary MATCH!");
 531         break;
 532
 533     case VARY_OTHER:
 534         /* This is not the correct entity for this request. We need
 535          * to requery the cache.
 536          */
 537         removeClientStoreReference(&sc, http);
 538         e = NULL;
 539         /* Note: varyEvalyateMatch updates the request with vary information
 540          * so we only get here once. (it also takes care of cancelling loops)
 541          */
 542         debugs(88, 2, "clientProcessHit: Vary detected!");
 543         clientGetMoreData(ourNode, http);
 544         return;
 545
 546     case VARY_CANCEL:
 547         /* varyEvaluateMatch found a object loop. Process as miss */
 548         debugs(88, DBG_IMPORTANT, "clientProcessHit: Vary object loop!");
 549         http->logType = LOG_TCP_MISS; // we lack a more precise LOG_*_MISS code
 550         processMiss();
 551         return;
 552     }
 553
 554     if (r->method == Http::METHOD_PURGE) {
 555         debugs(88, 5, "PURGE gets a HIT");
 556         removeClientStoreReference(&sc, http);
 557         e = NULL;
 558         purgeRequest();
 559         return;
 560     }
 561
 562     if (e->checkNegativeHit() && !r->flags.noCacheHack()) {
 563         debugs(88, 5, "negative-HIT");
 564         http->logType = LOG_TCP_NEGATIVE_HIT;
 565         sendMoreData(result);
 566     } else if (blockedHit()) {
 567         debugs(88, 5, "send_hit forces a MISS");
 568         http->logType = LOG_TCP_MISS;
 569         processMiss();
 570         return;
 571     } else if (!http->flags.internal && refreshCheckHTTP(e, r)) {
 572         debugs(88, 5, "clientCacheHit: in refreshCheck() block");
 573         /*
 574          * We hold a stale copy; it needs to be validated
 575          */
 576         /*
 577          * The 'needValidation' flag is used to prevent forwarding
 578          * loops between siblings.  If our copy of the object is stale,
 579          * then we should probably only use parents for the validation
 580          * request.  Otherwise two siblings could generate a loop if
 581          * both have a stale version of the object.
 582          */
 583         r->flags.needValidation = true;
 584
 585         if (e->lastmod < 0) {
 586             debugs(88, 3, "validate HIT object? NO. Missing Last-Modified header. Do MISS.");
 587             /*
 588              * Previous reply didn't have a Last-Modified header,
 589              * we cannot revalidate it.
 590              */
 591             http->logType = LOG_TCP_MISS;
 592             processMiss();
 593         } else if (r->flags.noCache) {
 594             debugs(88, 3, "validate HIT object? NO. Client sent CC:no-cache. Do CLIENT_REFRESH_MISS");
 595             /*
 596              * This did not match a refresh pattern that overrides no-cache
 597              * we should honour the client no-cache header.
 598              */
 599             http->logType = LOG_TCP_CLIENT_REFRESH_MISS;
 600             processMiss();
 601         } else if (r->url.getScheme() == AnyP::PROTO_HTTP) {
 602             debugs(88, 3, "validate HIT object? YES.");
 603             /*
 604              * Object needs to be revalidated
 605              * XXX This could apply to FTP as well, if Last-Modified is known.
 606              */
 607             processExpired();
 608         } else {
 609             debugs(88, 3, "validate HIT object? NO. Client protocol non-HTTP. Do MISS.");
 610             /*
 611              * We don't know how to re-validate other protocols. Handle
 612              * them as if the object has expired.
 613              */
 614             http->logType = LOG_TCP_MISS;
 615             processMiss();
 616         }
 617     } else if (r->conditional()) {
 618         debugs(88, 5, "conditional HIT");
 619         processConditional(result);
 620     } else {
 621         /*
 622          * plain ol' cache hit
 623          */
 624         debugs(88, 5, "plain old HIT");
 625
 626 #if USE_DELAY_POOLS
 627         if (e->store_status != STORE_OK)
 628             http->logType = LOG_TCP_MISS;
 629         else
 630 #endif
 631             if (e->mem_status == IN_MEMORY)
 632                 http->logType = LOG_TCP_MEM_HIT;
 633             else if (Config.onoff.offline)
 634                 http->logType = LOG_TCP_OFFLINE_HIT;
 635
 636         sendMoreData(result);
 637     }
 638 }
 639
 640 /**
 641  * Prepare to fetch the object as it's a cache miss of some kind.
 642  */
 643 void
 644 clientReplyContext::processMiss()
 645 {
 646     char *url = http->uri;
 647     HttpRequest *r = http->request;
 648     ErrorState *err = NULL;
 649     debugs(88, 4, r->method << ' ' << url);
 650
 651     /**
 652      * We might have a left-over StoreEntry from a failed cache hit
 653      * or IMS request.
 654      */
 655     if (http->storeEntry()) {
 656         if (EBIT_TEST(http->storeEntry()->flags, ENTRY_SPECIAL)) {
 657             debugs(88, DBG_CRITICAL, "clientProcessMiss: miss on a special object (" << url << ").");
 658             debugs(88, DBG_CRITICAL, "\tlog_type = " << http->logType.c_str());
 659             http->storeEntry()->dump(1);
 660         }
 661
 662         removeClientStoreReference(&sc, http);
 663     }
 664
 665     /** Check if its a PURGE request to be actioned. */
 666     if (r->method == Http::METHOD_PURGE) {
 667         purgeRequest();
 668         return;
 669     }
 670
 671     /** Check if its an 'OTHER' request. Purge all cached entries if so and continue. */
 672     if (r->method == Http::METHOD_OTHER) {
 673         purgeAllCached();
 674     }
 675
 676     /** Check if 'only-if-cached' flag is set. Action if so. */
 677     if (http->onlyIfCached()) {
 678         processOnlyIfCachedMiss();
 679         return;
 680     }
 681
 682     /// Deny loops
 683     if (r->flags.loopDetected) {
 684         http->al->http.code = Http::scForbidden;
 685         err = clientBuildError(ERR_ACCESS_DENIED, Http::scForbidden, NULL, http->getConn()->clientConnection->remote, http->request);
 686         createStoreEntry(r->method, RequestFlags());
 687         errorAppendEntry(http->storeEntry(), err);
 688         triggerInitialStoreRead();
 689         return;
 690     } else {
 691         assert(http->out.offset == 0);
 692         createStoreEntry(r->method, r->flags);
 693         triggerInitialStoreRead();
 694
 695         if (http->redirect.status) {
 696             HttpReply *rep = new HttpReply;
 697             http->logType = LOG_TCP_REDIRECT;
 698             http->storeEntry()->releaseRequest();
 699             rep->redirect(http->redirect.status, http->redirect.location);
 700             http->storeEntry()->replaceHttpReply(rep);
 701             http->storeEntry()->complete();
 702             return;
 703         }
 704
 705         assert(r->clientConnectionManager == http->getConn());
 706
 707         /** Start forwarding to get the new object from network */
 708         Comm::ConnectionPointer conn = http->getConn() != NULL ? http->getConn()->clientConnection : NULL;
 709         FwdState::Start(conn, http->storeEntry(), r, http->al);
 710     }
 711 }
 712
 713 /**
 714  * client issued a request with an only-if-cached cache-control directive;
 715  * we did not find a cached object that can be returned without
 716  *     contacting other servers;
 717  * respond with a 504 (Gateway Timeout) as suggested in [RFC 2068]
 718  */
 719 void
 720 clientReplyContext::processOnlyIfCachedMiss()
 721 {
 722     debugs(88, 4, http->request->method << ' ' << http->uri);
 723     http->al->http.code = Http::scGatewayTimeout;
 724     ErrorState *err = clientBuildError(ERR_ONLY_IF_CACHED_MISS, Http::scGatewayTimeout, NULL,
 725                                        http->getConn()->clientConnection->remote, http->request);
 726     removeClientStoreReference(&sc, http);
 727     startError(err);
 728 }
 729
 730 /// process conditional request from client
 731 void
 732 clientReplyContext::processConditional(StoreIOBuffer &result)
 733 {
 734     StoreEntry *const e = http->storeEntry();
 735
 736     if (e->getReply()->sline.status() != Http::scOkay) {
 737         debugs(88, 4, "clientReplyContext::processConditional: Reply code " <<
 738                e->getReply()->sline.status() << " != 200");
 739         http->logType = LOG_TCP_MISS;
 740         processMiss();
 741         return;
 742     }
 743
 744     HttpRequest &r = *http->request;
 745
 746     if (r.header.has(Http::HdrType::IF_MATCH) && !e->hasIfMatchEtag(r)) {
 747         // RFC 2616: reply with 412 Precondition Failed if If-Match did not match
 748         sendPreconditionFailedError();
 749         return;
 750     }
 751
 752     bool matchedIfNoneMatch = false;
 753     if (r.header.has(Http::HdrType::IF_NONE_MATCH)) {
 754         if (!e->hasIfNoneMatchEtag(r)) {
 755             // RFC 2616: ignore IMS if If-None-Match did not match
 756             r.flags.ims = false;
 757             r.ims = -1;
 758             r.imslen = 0;
 759             r.header.delById(Http::HdrType::IF_MODIFIED_SINCE);
 760             http->logType = LOG_TCP_MISS;
 761             sendMoreData(result);
 762             return;
 763         }
 764
 765         if (!r.flags.ims) {
 766             // RFC 2616: if If-None-Match matched and there is no IMS,
 767             // reply with 304 Not Modified or 412 Precondition Failed
 768             sendNotModifiedOrPreconditionFailedError();
 769             return;
 770         }
 771
 772         // otherwise check IMS below to decide if we reply with 304 or 412
 773         matchedIfNoneMatch = true;
 774     }
 775
 776     if (r.flags.ims) {
 777         // handle If-Modified-Since requests from the client
 778         if (e->modifiedSince(&r)) {
 779             http->logType = LOG_TCP_IMS_HIT;
 780             sendMoreData(result);
 781             return;
 782         }
 783
 784         if (matchedIfNoneMatch) {
 785             // If-None-Match matched, reply with 304 Not Modified or
 786             // 412 Precondition Failed
 787             sendNotModifiedOrPreconditionFailedError();
 788             return;
 789         }
 790
 791         // otherwise reply with 304 Not Modified
 792         sendNotModified();
 793     }
 794 }
 795
 796 /// whether squid.conf send_hit prevents us from serving this hit
 797 bool
 798 clientReplyContext::blockedHit() const
 799 {
 800     if (!Config.accessList.sendHit)
 801         return false; // hits are not blocked by default
 802
 803     if (http->flags.internal)
 804         return false; // internal content "hits" cannot be blocked
 805
 806     if (const HttpReply *rep = http->storeEntry()->getReply()) {
 807         std::unique_ptr<ACLFilledChecklist> chl(clientAclChecklistCreate(Config.accessList.sendHit, http));
 808         chl->reply = const_cast<HttpReply*>(rep); // ACLChecklist API bug
 809         HTTPMSGLOCK(chl->reply);
 810         return chl->fastCheck() != ACCESS_ALLOWED; // when in doubt, block
 811     }
 812
 813     // This does not happen, I hope, because we are called from CacheHit, which
 814     // is called via a storeClientCopy() callback, and store should initialize
 815     // the reply before calling that callback.
 816     debugs(88, 3, "Missing reply!");
 817     return false;
 818 }
 819
 820 void
 821 clientReplyContext::purgeRequestFindObjectToPurge()
 822 {
 823     /* Try to find a base entry */
 824     http->flags.purging = true;
 825     lookingforstore = 1;
 826
 827     // TODO: can we use purgeAllCached() here instead of doing the
 828     // getPublicByRequestMethod() dance?
 829     StoreEntry::getPublicByRequestMethod(this, http->request, Http::METHOD_GET);
 830 }
 831
 832 // Purges all entries with a given url
 833 // TODO: move to SideAgent parent, when we have one
 834 /*
 835  * We probably cannot purge Vary-affected responses because their MD5
 836  * keys depend on vary headers.
 837  */
 838 void
 839 purgeEntriesByUrl(HttpRequest * req, const char *url)
 840 {
 841 #if USE_HTCP
 842     bool get_or_head_sent = false;
 843 #endif
 844
 845     for (HttpRequestMethod m(Http::METHOD_NONE); m != Http::METHOD_ENUM_END; ++m) {
 846         if (m.respMaybeCacheable()) {
 847             if (StoreEntry *entry = storeGetPublic(url, m)) {
 848                 debugs(88, 5, "purging " << *entry << ' ' << m << ' ' << url);
 849 #if USE_HTCP
 850                 neighborsHtcpClear(entry, url, req, m, HTCP_CLR_INVALIDATION);
 851                 if (m == Http::METHOD_GET || m == Http::METHOD_HEAD) {
 852                     get_or_head_sent = true;
 853                 }
 854 #endif
 855                 entry->release();
 856             }
 857         }
 858     }
 859
 860 #if USE_HTCP
 861     if (!get_or_head_sent) {
 862         neighborsHtcpClear(NULL, url, req, HttpRequestMethod(Http::METHOD_GET), HTCP_CLR_INVALIDATION);
 863     }
 864 #endif
 865 }
 866
 867 void
 868 clientReplyContext::purgeAllCached()
 869 {
 870     // XXX: performance regression, c_str() reallocates
 871     SBuf url(http->request->effectiveRequestUri());
 872     purgeEntriesByUrl(http->request, url.c_str());
 873 }
 874
 875 void
 876 clientReplyContext::created(StoreEntry *newEntry)
 877 {
 878     if (lookingforstore == 1)
 879         purgeFoundGet(newEntry);
 880     else if (lookingforstore == 2)
 881         purgeFoundHead(newEntry);
 882     else if (lookingforstore == 3)
 883         purgeDoPurgeGet(newEntry);
 884     else if (lookingforstore == 4)
 885         purgeDoPurgeHead(newEntry);
 886     else if (lookingforstore == 5)
 887         identifyFoundObject(newEntry);
 888 }
 889
 890 void
 891 clientReplyContext::purgeFoundGet(StoreEntry *newEntry)
 892 {
 893     if (newEntry->isNull()) {
 894         lookingforstore = 2;
 895         StoreEntry::getPublicByRequestMethod(this, http->request, Http::METHOD_HEAD);
 896     } else
 897         purgeFoundObject (newEntry);
 898 }
 899
 900 void
 901 clientReplyContext::purgeFoundHead(StoreEntry *newEntry)
 902 {
 903     if (newEntry->isNull())
 904         purgeDoMissPurge();
 905     else
 906         purgeFoundObject (newEntry);
 907 }
 908
 909 void
 910 clientReplyContext::purgeFoundObject(StoreEntry *entry)
 911 {
 912     assert (entry && !entry->isNull());
 913
 914     if (EBIT_TEST(entry->flags, ENTRY_SPECIAL)) {
 915         http->logType = LOG_TCP_DENIED;
 916         ErrorState *err = clientBuildError(ERR_ACCESS_DENIED, Http::scForbidden, NULL,
 917                                            http->getConn()->clientConnection->remote, http->request);
 918         startError(err);
 919         return; // XXX: leaking unused entry if some store does not keep it
 920     }
 921
 922     StoreIOBuffer localTempBuffer;
 923     /* Swap in the metadata */
 924     http->storeEntry(entry);
 925
 926     http->storeEntry()->lock("clientReplyContext::purgeFoundObject");
 927     http->storeEntry()->createMemObject(storeId(), http->log_uri,
 928                                         http->request->method);
 929
 930     sc = storeClientListAdd(http->storeEntry(), this);
 931
 932     http->logType = LOG_TCP_HIT;
 933
 934     reqofs = 0;
 935
 936     localTempBuffer.offset = http->out.offset;
 937
 938     localTempBuffer.length = next()->readBuffer.length;
 939
 940     localTempBuffer.data = next()->readBuffer.data;
 941
 942     storeClientCopy(sc, http->storeEntry(),
 943                     localTempBuffer, CacheHit, this);
 944 }
 945
 946 void
 947 clientReplyContext::purgeRequest()
 948 {
 949     debugs(88, 3, "Config2.onoff.enable_purge = " <<
 950            Config2.onoff.enable_purge);
 951
 952     if (!Config2.onoff.enable_purge) {
 953         http->logType = LOG_TCP_DENIED;
 954         ErrorState *err = clientBuildError(ERR_ACCESS_DENIED, Http::scForbidden, NULL, http->getConn()->clientConnection->remote, http->request);
 955         startError(err);
 956         return;
 957     }
 958
 959     /* Release both IP cache */
 960     ipcacheInvalidate(http->request->url.host());
 961
 962     if (!http->flags.purging)
 963         purgeRequestFindObjectToPurge();
 964     else
 965         purgeDoMissPurge();
 966 }
 967
 968 void
 969 clientReplyContext::purgeDoMissPurge()
 970 {
 971     http->logType = LOG_TCP_MISS;
 972     lookingforstore = 3;
 973     StoreEntry::getPublicByRequestMethod(this,http->request, Http::METHOD_GET);
 974 }
 975
 976 void
 977 clientReplyContext::purgeDoPurgeGet(StoreEntry *newEntry)
 978 {
 979     assert (newEntry);
 980     /* Move to new() when that is created */
 981     purgeStatus = Http::scNotFound;
 982
 983     if (!newEntry->isNull()) {
 984         /* Release the cached URI */
 985         debugs(88, 4, "clientPurgeRequest: GET '" << newEntry->url() << "'" );
 986 #if USE_HTCP
 987         neighborsHtcpClear(newEntry, NULL, http->request, HttpRequestMethod(Http::METHOD_GET), HTCP_CLR_PURGE);
 988 #endif
 989         newEntry->release();
 990         purgeStatus = Http::scOkay;
 991     }
 992
 993     lookingforstore = 4;
 994     StoreEntry::getPublicByRequestMethod(this, http->request, Http::METHOD_HEAD);
 995 }
 996
 997 void
 998 clientReplyContext::purgeDoPurgeHead(StoreEntry *newEntry)
 999 {
1000     if (newEntry && !newEntry->isNull()) {
1001         debugs(88, 4, "HEAD " << newEntry->url());
1002 #if USE_HTCP
1003         neighborsHtcpClear(newEntry, NULL, http->request, HttpRequestMethod(Http::METHOD_HEAD), HTCP_CLR_PURGE);
1004 #endif
1005         newEntry->release();
1006         purgeStatus = Http::scOkay;
1007     }
1008
1009     /* And for Vary, release the base URI if none of the headers was included in the request */
1010
1011     if (http->request->vary_headers
1012             && !strstr(http->request->vary_headers, "=")) {
1013         // XXX: performance regression, c_str() reallocates
1014         SBuf tmp(http->request->effectiveRequestUri());
1015         StoreEntry *entry = storeGetPublic(tmp.c_str(), Http::METHOD_GET);
1016
1017         if (entry) {
1018             debugs(88, 4, "Vary GET " << entry->url());
1019 #if USE_HTCP
1020             neighborsHtcpClear(entry, NULL, http->request, HttpRequestMethod(Http::METHOD_GET), HTCP_CLR_PURGE);
1021 #endif
1022             entry->release();
1023             purgeStatus = Http::scOkay;
1024         }
1025
1026         entry = storeGetPublic(tmp.c_str(), Http::METHOD_HEAD);
1027
1028         if (entry) {
1029             debugs(88, 4, "Vary HEAD " << entry->url());
1030 #if USE_HTCP
1031             neighborsHtcpClear(entry, NULL, http->request, HttpRequestMethod(Http::METHOD_HEAD), HTCP_CLR_PURGE);
1032 #endif
1033             entry->release();
1034             purgeStatus = Http::scOkay;
1035         }
1036     }
1037
1038     /*
1039      * Make a new entry to hold the reply to be written
1040      * to the client.
1041      */
1042     /* FIXME: This doesn't need to go through the store. Simply
1043      * push down the client chain
1044      */
1045     createStoreEntry(http->request->method, RequestFlags());
1046
1047     triggerInitialStoreRead();
1048
1049     HttpReply *rep = new HttpReply;
1050     rep->setHeaders(purgeStatus, NULL, NULL, 0, 0, -1);
1051     http->storeEntry()->replaceHttpReply(rep);
1052     http->storeEntry()->complete();
1053 }
1054
1055 void
1056 clientReplyContext::traceReply(clientStreamNode * node)
1057 {
1058     clientStreamNode *nextNode = (clientStreamNode *)node->node.next->data;
1059     StoreIOBuffer localTempBuffer;
1060     createStoreEntry(http->request->method, RequestFlags());
1061     localTempBuffer.offset = nextNode->readBuffer.offset + headers_sz;
1062     localTempBuffer.length = nextNode->readBuffer.length;
1063     localTempBuffer.data = nextNode->readBuffer.data;
1064     storeClientCopy(sc, http->storeEntry(),
1065                     localTempBuffer, SendMoreData, this);
1066     http->storeEntry()->releaseRequest();
1067     http->storeEntry()->buffer();
1068     HttpReply *rep = new HttpReply;
1069     rep->setHeaders(Http::scOkay, NULL, "text/plain", http->request->prefixLen(), 0, squid_curtime);
1070     http->storeEntry()->replaceHttpReply(rep);
1071     http->request->swapOut(http->storeEntry());
1072     http->storeEntry()->complete();
1073 }
1074
1075 #define SENDING_BODY 0
1076 #define SENDING_HDRSONLY 1
1077 int
1078 clientReplyContext::checkTransferDone()
1079 {
1080     StoreEntry *entry = http->storeEntry();
1081
1082     if (entry == NULL)
1083         return 0;
1084
1085     /*
1086      * For now, 'done_copying' is used for special cases like
1087      * Range and HEAD requests.
1088      */
1089     if (http->flags.done_copying)
1090         return 1;
1091
1092     if (http->request->flags.chunkedReply && !flags.complete) {
1093         // last-chunk was not sent
1094         return 0;
1095     }
1096
1097     /*
1098      * Handle STORE_OK objects.
1099      * objectLen(entry) will be set proprely.
1100      * RC: Does objectLen(entry) include the Headers?
1101      * RC: Yes.
1102      */
1103     if (entry->store_status == STORE_OK) {
1104         return storeOKTransferDone();
1105     } else {
1106         return storeNotOKTransferDone();
1107     }
1108 }
1109
1110 int
1111 clientReplyContext::storeOKTransferDone() const
1112 {
1113     assert(http->storeEntry()->objectLen() >= 0);
1114     assert(http->storeEntry()->objectLen() >= headers_sz);
1115     if (http->out.offset >= http->storeEntry()->objectLen() - headers_sz) {
1116         debugs(88,3,HERE << "storeOKTransferDone " <<
1117                " out.offset=" << http->out.offset <<
1118                " objectLen()=" << http->storeEntry()->objectLen() <<
1119                " headers_sz=" << headers_sz);
1120         return 1;
1121     }
1122
1123     return 0;
1124 }
1125
1126 int
1127 clientReplyContext::storeNotOKTransferDone() const
1128 {
1129     /*
1130      * Now, handle STORE_PENDING objects
1131      */
1132     MemObject *mem = http->storeEntry()->mem_obj;
1133     assert(mem != NULL);
1134     assert(http->request != NULL);
1135     /* mem->reply was wrong because it uses the UPSTREAM header length!!! */
1136     HttpReply const *curReply = mem->getReply();
1137
1138     if (headers_sz == 0)
1139         /* haven't found end of headers yet */
1140         return 0;
1141
1142     /*
1143      * Figure out how much data we are supposed to send.
1144      * If we are sending a body and we don't have a content-length,
1145      * then we must wait for the object to become STORE_OK.
1146      */
1147     if (curReply->content_length < 0)
1148         return 0;
1149
1150     int64_t expectedLength = curReply->content_length + http->out.headers_sz;
1151
1152     if (http->out.size < expectedLength)
1153         return 0;
1154     else {
1155         debugs(88,3,HERE << "storeNotOKTransferDone " <<
1156                " out.size=" << http->out.size <<
1157                " expectedLength=" << expectedLength);
1158         return 1;
1159     }
1160 }
1161
1162 /* A write has completed, what is the next status based on the
1163  * canonical request data?
1164  * 1 something is wrong
1165  * 0 nothing is wrong.
1166  *
1167  */
1168 int
1169 clientHttpRequestStatus(int fd, ClientHttpRequest const *http)
1170 {
1171 #if SIZEOF_INT64_T == 4
1172     if (http->out.size > 0x7FFF0000) {
1173         debugs(88, DBG_IMPORTANT, "WARNING: closing FD " << fd << " to prevent out.size counter overflow");
1174         debugs(88, DBG_IMPORTANT, "\tclient " << http->getConn()->peer);
1175         debugs(88, DBG_IMPORTANT, "\treceived " << http->out.size << " bytes");
1176         debugs(88, DBG_IMPORTANT, "\tURI " << http->log_uri);
1177         return 1;
1178     }
1179
1180     if (http->out.offset > 0x7FFF0000) {
1181         debugs(88, DBG_IMPORTANT, "WARNING: closing FD " << fd < " to prevent out.offset counter overflow");
1182         debugs(88, DBG_IMPORTANT, "\tclient " << http->getConn()->peer);
1183         debugs(88, DBG_IMPORTANT, "\treceived " << http->out.size << " bytes, offset " << http->out.offset);
1184         debugs(88, DBG_IMPORTANT, "\tURI " << http->log_uri);
1185         return 1;
1186     }
1187
1188 #endif
1189     return 0;
1190 }
1191
1192 /* Preconditions:
1193  * *http is a valid structure.
1194  * fd is either -1, or an open fd.
1195  *
1196  * TODO: enumify this
1197  *
1198  * This function is used by any http request sink, to determine the status
1199  * of the object.
1200  */
1201 clientStream_status_t
1202 clientReplyStatus(clientStreamNode * aNode, ClientHttpRequest * http)
1203 {
1204     clientReplyContext *context = dynamic_cast<clientReplyContext *>(aNode->data.getRaw());
1205     assert (context);
1206     assert (context->http == http);
1207     return context->replyStatus();
1208 }
1209
1210 clientStream_status_t
1211 clientReplyContext::replyStatus()
1212 {
1213     int done;
1214     /* Here because lower nodes don't need it */
1215
1216     if (http->storeEntry() == NULL) {
1217         debugs(88, 5, "clientReplyStatus: no storeEntry");
1218         return STREAM_FAILED;   /* yuck, but what can we do? */
1219     }
1220
1221     if (EBIT_TEST(http->storeEntry()->flags, ENTRY_ABORTED)) {
1222         /* TODO: Could upstream read errors (result.flags.error) be
1223          * lost, and result in undersize requests being considered
1224          * complete. Should we tcp reset such connections ?
1225          */
1226         debugs(88, 5, "clientReplyStatus: aborted storeEntry");
1227         return STREAM_FAILED;
1228     }
1229
1230     if ((done = checkTransferDone()) != 0 || flags.complete) {
1231         debugs(88, 5, "clientReplyStatus: transfer is DONE: " << done << flags.complete);
1232         /* Ok we're finished, but how? */
1233
1234         const int64_t expectedBodySize =
1235             http->storeEntry()->getReply()->bodySize(http->request->method);
1236         if (!http->request->flags.proxyKeepalive && expectedBodySize < 0) {
1237             debugs(88, 5, "clientReplyStatus: closing, content_length < 0");
1238             return STREAM_FAILED;
1239         }
1240
1241         if (EBIT_TEST(http->storeEntry()->flags, ENTRY_BAD_LENGTH)) {
1242             debugs(88, 5, "clientReplyStatus: truncated response body");
1243             return STREAM_UNPLANNED_COMPLETE;
1244         }
1245
1246         if (!done) {
1247             debugs(88, 5, "clientReplyStatus: closing, !done, but read 0 bytes");
1248             return STREAM_FAILED;
1249         }
1250
1251         if (expectedBodySize >= 0 && !http->gotEnough()) {
1252             debugs(88, 5, "clientReplyStatus: client didn't get all it expected");
1253             return STREAM_UNPLANNED_COMPLETE;
1254         }
1255
1256         debugs(88, 5, "clientReplyStatus: stream complete; keepalive=" <<
1257                http->request->flags.proxyKeepalive);
1258         return STREAM_COMPLETE;
1259     }
1260
1261     // XXX: Should this be checked earlier? We could return above w/o checking.
1262     if (reply->receivedBodyTooLarge(*http->request, http->out.offset - 4096)) {
1263         /* 4096 is a margin for the HTTP headers included in out.offset */
1264         debugs(88, 5, "clientReplyStatus: client reply body is too large");
1265         return STREAM_FAILED;
1266     }
1267
1268     return STREAM_NONE;
1269 }
1270
1271 /* Responses with no body will not have a content-type header,
1272  * which breaks the rep_mime_type acl, which
1273  * coincidentally, is the most common acl for reply access lists.
1274  * A better long term fix for this is to allow acl matchs on the various
1275  * status codes, and then supply a default ruleset that puts these
1276  * codes before any user defines access entries. That way the user
1277  * can choose to block these responses where appropriate, but won't get
1278  * mysterious breakages.
1279  */
1280 bool
1281 clientReplyContext::alwaysAllowResponse(Http::StatusCode sline) const
1282 {
1283     bool result;
1284
1285     switch (sline) {
1286
1287     case Http::scContinue:
1288
1289     case Http::scSwitchingProtocols:
1290
1291     case Http::scProcessing:
1292
1293     case Http::scNoContent:
1294
1295     case Http::scNotModified:
1296         result = true;
1297         break;
1298
1299     default:
1300         result = false;
1301     }
1302
1303     return result;
1304 }
1305
1306 /**
1307  * Generate the reply headers sent to client.
1308  *
1309  * Filters out unwanted entries and hop-by-hop from original reply header
1310  * then adds extra entries if we have more info than origin server
1311  * then adds Squid specific entries
1312  */
1313 void
1314 clientReplyContext::buildReplyHeader()
1315 {
1316     HttpHeader *hdr = &reply->header;
1317     const bool is_hit = http->logType.isTcpHit();
1318     HttpRequest *request = http->request;
1319 #if DONT_FILTER_THESE
1320     /* but you might want to if you run Squid as an HTTP accelerator */
1321     /* hdr->delById(HDR_ACCEPT_RANGES); */
1322     hdr->delById(HDR_ETAG);
1323 #endif
1324
1325     if (is_hit)
1326         hdr->delById(Http::HdrType::SET_COOKIE);
1327     // TODO: RFC 2965 : Must honour Cache-Control: no-cache="set-cookie2" and remove header.
1328
1329     // if there is not configured a peer proxy with login=PASS or login=PASSTHRU option enabled
1330     // remove the Proxy-Authenticate header
1331     if ( !request->peer_login || (strcmp(request->peer_login,"PASS") != 0 && strcmp(request->peer_login,"PASSTHRU") != 0))
1332         reply->header.delById(Http::HdrType::PROXY_AUTHENTICATE);
1333
1334     reply->header.removeHopByHopEntries();
1335
1336     //    if (request->range)
1337     //      clientBuildRangeHeader(http, reply);
1338
1339     /*
1340      * Add a estimated Age header on cache hits.
1341      */
1342     if (is_hit) {
1343         /*
1344          * Remove any existing Age header sent by upstream caches
1345          * (note that the existing header is passed along unmodified
1346          * on cache misses)
1347          */
1348         hdr->delById(Http::HdrType::AGE);
1349         /*
1350          * This adds the calculated object age. Note that the details of the
1351          * age calculation is performed by adjusting the timestamp in
1352          * StoreEntry::timestampsSet(), not here.
1353          */
1354         if (EBIT_TEST(http->storeEntry()->flags, ENTRY_SPECIAL)) {
1355             hdr->delById(Http::HdrType::DATE);
1356             hdr->insertTime(Http::HdrType::DATE, squid_curtime);
1357         } else if (http->getConn() && http->getConn()->port->actAsOrigin) {
1358             // Swap the Date: header to current time if we are simulating an origin
1359             HttpHeaderEntry *h = hdr->findEntry(Http::HdrType::DATE);
1360             if (h)
1361                 hdr->putExt("X-Origin-Date", h->value.termedBuf());
1362             hdr->delById(Http::HdrType::DATE);
1363             hdr->insertTime(Http::HdrType::DATE, squid_curtime);
1364             h = hdr->findEntry(Http::HdrType::EXPIRES);
1365             if (h && http->storeEntry()->expires >= 0) {
1366                 hdr->putExt("X-Origin-Expires", h->value.termedBuf());
1367                 hdr->delById(Http::HdrType::EXPIRES);
1368                 hdr->insertTime(Http::HdrType::EXPIRES, squid_curtime + http->storeEntry()->expires - http->storeEntry()->timestamp);
1369             }
1370             if (http->storeEntry()->timestamp <= squid_curtime) {
1371                 // put X-Cache-Age: instead of Age:
1372                 char age[64];
1373                 snprintf(age, sizeof(age), "%" PRId64, static_cast<int64_t>(squid_curtime - http->storeEntry()->timestamp));
1374                 hdr->putExt("X-Cache-Age", age);
1375             }
1376         } else if (http->storeEntry()->timestamp <= squid_curtime) {
1377             hdr->putInt(Http::HdrType::AGE,
1378                         squid_curtime - http->storeEntry()->timestamp);
1379             /* Signal old objects.  NB: rfc 2616 is not clear,
1380              * by implication, on whether we should do this to all
1381              * responses, or only cache hits.
1382              * 14.46 states it ONLY applys for heuristically caclulated
1383              * freshness values, 13.2.4 doesn't specify the same limitation.
1384              * We interpret RFC 2616 under the combination.
1385              */
1386             /* TODO: if maxage or s-maxage is present, don't do this */
1387
1388             if (squid_curtime - http->storeEntry()->timestamp >= 86400) {
1389                 char tbuf[512];
1390                 snprintf (tbuf, sizeof(tbuf), "%s %s %s",
1391                           "113", ThisCache,
1392                           "This cache hit is still fresh and more than 1 day old");
1393                 hdr->putStr(Http::HdrType::WARNING, tbuf);
1394             }
1395         }
1396     }
1397
1398     /* RFC 2616: Section 14.18
1399      *
1400      * Add a Date: header if missing.
1401      * We have access to a clock therefore are required to amend any shortcoming in servers.
1402      *
1403      * NP: done after Age: to prevent ENTRY_SPECIAL double-handling this header.
1404      */
1405     if ( !hdr->has(Http::HdrType::DATE) ) {
1406         if (!http->storeEntry())
1407             hdr->insertTime(Http::HdrType::DATE, squid_curtime);
1408         else if (http->storeEntry()->timestamp > 0)
1409             hdr->insertTime(Http::HdrType::DATE, http->storeEntry()->timestamp);
1410         else {
1411             debugs(88,DBG_IMPORTANT,"BUG 3279: HTTP reply without Date:");
1412             /* dump something useful about the problem */
1413             http->storeEntry()->dump(DBG_IMPORTANT);
1414         }
1415     }
1416
1417     // add Warnings required by RFC 2616 if serving a stale hit
1418     if (http->request->flags.staleIfHit && http->logType.isTcpHit()) {
1419         hdr->putWarning(110, "Response is stale");
1420         if (http->request->flags.needValidation)
1421             hdr->putWarning(111, "Revalidation failed");
1422     }
1423
1424     /* Filter unproxyable authentication types */
1425     if (http->logType.oldType != LOG_TCP_DENIED &&
1426             hdr->has(Http::HdrType::WWW_AUTHENTICATE)) {
1427         HttpHeaderPos pos = HttpHeaderInitPos;
1428         HttpHeaderEntry *e;
1429
1430         int connection_auth_blocked = 0;
1431         while ((e = hdr->getEntry(&pos))) {
1432             if (e->id == Http::HdrType::WWW_AUTHENTICATE) {
1433                 const char *value = e->value.rawBuf();
1434
1435                 if ((strncasecmp(value, "NTLM", 4) == 0 &&
1436                         (value[4] == '\0' || value[4] == ' '))
1437                         ||
1438                         (strncasecmp(value, "Negotiate", 9) == 0 &&
1439                          (value[9] == '\0' || value[9] == ' '))
1440                         ||
1441                         (strncasecmp(value, "Kerberos", 8) == 0 &&
1442                          (value[8] == '\0' || value[8] == ' '))) {
1443                     if (request->flags.connectionAuthDisabled) {
1444                         hdr->delAt(pos, connection_auth_blocked);
1445                         continue;
1446                     }
1447                     request->flags.mustKeepalive = true;
1448                     if (!request->flags.accelerated && !request->flags.intercepted) {
1449                         httpHeaderPutStrf(hdr, Http::HdrType::PROXY_SUPPORT, "Session-Based-Authentication");
1450                         /*
1451                           We send "Connection: Proxy-Support" header to mark
1452                           Proxy-Support as a hop-by-hop header for intermediaries that do not
1453                           understand the semantics of this header. The RFC should have included
1454                           this recommendation.
1455                         */
1456                         httpHeaderPutStrf(hdr, Http::HdrType::CONNECTION, "Proxy-support");
1457                     }
1458                     break;
1459                 }
1460             }
1461         }
1462
1463         if (connection_auth_blocked)
1464             hdr->refreshMask();
1465     }
1466
1467 #if USE_AUTH
1468     /* Handle authentication headers */
1469     if (http->logType.oldType == LOG_TCP_DENIED &&
1470             ( reply->sline.status() == Http::scProxyAuthenticationRequired ||
1471               reply->sline.status() == Http::scUnauthorized)
1472        ) {
1473         /* Add authentication header */
1474         /*! \todo alter errorstate to be accel on|off aware. The 0 on the next line
1475          * depends on authenticate behaviour: all schemes to date send no extra
1476          * data on 407/401 responses, and do not check the accel state on 401/407
1477          * responses
1478          */
1479         authenticateFixHeader(reply, request->auth_user_request, request, 0, 1);
1480     } else if (request->auth_user_request != NULL)
1481         authenticateFixHeader(reply, request->auth_user_request, request, http->flags.accel, 0);
1482 #endif
1483
1484     /* Append X-Cache */
1485     httpHeaderPutStrf(hdr, Http::HdrType::X_CACHE, "%s from %s",
1486                       is_hit ? "HIT" : "MISS", getMyHostname());
1487
1488 #if USE_CACHE_DIGESTS
1489     /* Append X-Cache-Lookup: -- temporary hack, to be removed @?@ @?@ */
1490     httpHeaderPutStrf(hdr, Http::HdrType::X_CACHE_LOOKUP, "%s from %s:%d",
1491                       lookup_type ? lookup_type : "NONE",
1492                       getMyHostname(), getMyPort());
1493
1494 #endif
1495
1496     const bool maySendChunkedReply = !request->multipartRangeRequest() &&
1497                                      reply->sline.protocol == AnyP::PROTO_HTTP && // response is HTTP
1498                                      (request->http_ver >= Http::ProtocolVersion(1,1));
1499
1500     /* Check whether we should send keep-alive */
1501     if (!Config.onoff.error_pconns && reply->sline.status() >= 400 && !request->flags.mustKeepalive) {
1502         debugs(33, 3, "clientBuildReplyHeader: Error, don't keep-alive");
1503         request->flags.proxyKeepalive = false;
1504     } else if (!Config.onoff.client_pconns && !request->flags.mustKeepalive) {
1505         debugs(33, 2, "clientBuildReplyHeader: Connection Keep-Alive not requested by admin or client");
1506         request->flags.proxyKeepalive = false;
1507     } else if (request->flags.proxyKeepalive && shutting_down) {
1508         debugs(88, 3, "clientBuildReplyHeader: Shutting down, don't keep-alive.");
1509         request->flags.proxyKeepalive = false;
1510     } else if (request->flags.connectionAuth && !reply->keep_alive) {
1511         debugs(33, 2, "clientBuildReplyHeader: Connection oriented auth but server side non-persistent");
1512         request->flags.proxyKeepalive = false;
1513     } else if (reply->bodySize(request->method) < 0 && !maySendChunkedReply) {
1514         debugs(88, 3, "clientBuildReplyHeader: can't keep-alive, unknown body size" );
1515         request->flags.proxyKeepalive = false;
1516     } else if (fdUsageHigh()&& !request->flags.mustKeepalive) {
1517         debugs(88, 3, "clientBuildReplyHeader: Not many unused FDs, can't keep-alive");
1518         request->flags.proxyKeepalive = false;
1519     } else if (request->flags.sslBumped && !reply->persistent()) {
1520         // We do not really have to close, but we pretend we are a tunnel.
1521         debugs(88, 3, "clientBuildReplyHeader: bumped reply forces close");
1522         request->flags.proxyKeepalive = false;
1523     } else if (request->pinnedConnection() && !reply->persistent()) {
1524         // The peer wants to close the pinned connection
1525         debugs(88, 3, "pinned reply forces close");
1526         request->flags.proxyKeepalive = false;
1527     } else if (http->getConn()) {
1528         ConnStateData * conn = http->getConn();
1529         if (!Comm::IsConnOpen(conn->port->listenConn)) {
1530             // The listening port closed because of a reconfigure
1531             debugs(88, 3, "listening port closed");
1532             request->flags.proxyKeepalive = false;
1533         }
1534     }
1535
1536     // Decide if we send chunked reply
1537     if (maySendChunkedReply &&
1538             request->flags.proxyKeepalive &&
1539             reply->bodySize(request->method) < 0) {
1540         debugs(88, 3, "clientBuildReplyHeader: chunked reply");
1541         request->flags.chunkedReply = true;
1542         hdr->putStr(Http::HdrType::TRANSFER_ENCODING, "chunked");
1543     }
1544
1545     /* Append VIA */
1546     if (Config.onoff.via) {
1547         LOCAL_ARRAY(char, bbuf, MAX_URL + 32);
1548         String strVia;
1549         hdr->getList(Http::HdrType::VIA, &strVia);
1550         snprintf(bbuf, MAX_URL + 32, "%d.%d %s",
1551                  reply->sline.version.major,
1552                  reply->sline.version.minor,
1553                  ThisCache);
1554         strListAdd(&strVia, bbuf, ',');
1555         hdr->delById(Http::HdrType::VIA);
1556         hdr->putStr(Http::HdrType::VIA, strVia.termedBuf());
1557     }
1558     /* Signal keep-alive or close explicitly */
1559     hdr->putStr(Http::HdrType::CONNECTION, request->flags.proxyKeepalive ? "keep-alive" : "close");
1560
1561 #if ADD_X_REQUEST_URI
1562     /*
1563      * Knowing the URI of the request is useful when debugging persistent
1564      * connections in a client; we cannot guarantee the order of http headers,
1565      * but X-Request-URI is likely to be the very last header to ease use from a
1566      * debugger [hdr->entries.count-1].
1567      */
1568     hdr->putStr(Http::HdrType::X_REQUEST_URI,
1569                 http->memOjbect()->url ? http->memObject()->url : http->uri);
1570
1571 #endif
1572
1573     /* Surrogate-Control requires Surrogate-Capability from upstream to pass on */
1574     if ( hdr->has(Http::HdrType::SURROGATE_CONTROL) ) {
1575         if (!request->header.has(Http::HdrType::SURROGATE_CAPABILITY)) {
1576             hdr->delById(Http::HdrType::SURROGATE_CONTROL);
1577         }
1578         /* TODO: else case: drop any controls intended specifically for our surrogate ID */
1579     }
1580
1581     httpHdrMangleList(hdr, request, ROR_REPLY);
1582 }
1583
1584 void
1585 clientReplyContext::cloneReply()
1586 {
1587     assert(reply == NULL);
1588
1589     reply = http->storeEntry()->getReply()->clone();
1590     HTTPMSGLOCK(reply);
1591
1592     if (reply->sline.protocol == AnyP::PROTO_HTTP) {
1593         /* RFC 2616 requires us to advertise our version (but only on real HTTP traffic) */
1594         reply->sline.version = Http::ProtocolVersion();
1595     }
1596
1597     /* do header conversions */
1598     buildReplyHeader();
1599 }
1600
1601 /// Safely disposes of an entry pointing to a cache hit that we do not want.
1602 /// We cannot just ignore the entry because it may be locking or otherwise
1603 /// holding an associated cache resource of some sort.
1604 void
1605 clientReplyContext::forgetHit()
1606 {
1607     StoreEntry *e = http->storeEntry();
1608     assert(e); // or we are not dealing with a hit
1609     // We probably have not locked the entry earlier, unfortunately. We lock it
1610     // now so that we can unlock two lines later (and trigger cleanup).
1611     // Ideally, ClientHttpRequest::storeEntry() should lock/unlock, but it is
1612     // used so inconsistently that simply adding locking there leads to bugs.
1613     e->lock("clientReplyContext::forgetHit");
1614     http->storeEntry(NULL);
1615     e->unlock("clientReplyContext::forgetHit"); // may delete e
1616 }
1617
1618 void
1619 clientReplyContext::identifyStoreObject()
1620 {
1621     HttpRequest *r = http->request;
1622
1623     if (r->flags.cachable || r->flags.internal) {
1624         lookingforstore = 5;
1625         StoreEntry::getPublicByRequest (this, r);
1626     } else {
1627         identifyFoundObject (NullStoreEntry::getInstance());
1628     }
1629 }
1630
1631 /**
1632  * Check state of the current StoreEntry object.
1633  * to see if we can determine the final status of the request.
1634  */
1635 void
1636 clientReplyContext::identifyFoundObject(StoreEntry *newEntry)
1637 {
1638     StoreEntry *e = newEntry;
1639     HttpRequest *r = http->request;
1640
1641     /** \li If the entry received isNull() then we ignore it. */
1642     if (e->isNull()) {
1643         http->storeEntry(NULL);
1644     } else {
1645         http->storeEntry(e);
1646     }
1647
1648     e = http->storeEntry();
1649
1650     /* Release IP-cache entries on reload */
1651     /** \li If the request has no-cache flag set or some no_cache HACK in operation we
1652       * 'invalidate' the cached IP entries for this request ???
1653       */
1654     if (r->flags.noCache || r->flags.noCacheHack())
1655         ipcacheInvalidateNegative(r->url.host());
1656
1657 #if USE_CACHE_DIGESTS
1658     lookup_type = http->storeEntry() ? "HIT" : "MISS";
1659 #endif
1660
1661     if (NULL == http->storeEntry()) {
1662         /** \li If no StoreEntry object is current assume this object isn't in the cache set MISS*/
1663         debugs(85, 3, "StoreEntry is NULL -  MISS");
1664         http->logType = LOG_TCP_MISS;
1665         doGetMoreData();
1666         return;
1667     }
1668
1669     if (Config.onoff.offline) {
1670         /** \li If we are running in offline mode set to HIT */
1671         debugs(85, 3, "offline HIT " << *e);
1672         http->logType = LOG_TCP_HIT;
1673         doGetMoreData();
1674         return;
1675     }
1676
1677     if (http->redirect.status) {
1678         /** \li If redirection status is True force this to be a MISS */
1679         debugs(85, 3, "REDIRECT status forced StoreEntry to NULL (no body on 3XX responses) " << *e);
1680         forgetHit();
1681         http->logType = LOG_TCP_REDIRECT;
1682         doGetMoreData();
1683         return;
1684     }
1685
1686     if (!e->validToSend()) {
1687         debugs(85, 3, "!storeEntryValidToSend MISS " << *e);
1688         forgetHit();
1689         http->logType = LOG_TCP_MISS;
1690         doGetMoreData();
1691         return;
1692     }
1693
1694     if (EBIT_TEST(e->flags, ENTRY_SPECIAL)) {
1695         /* \li Special entries are always hits, no matter what the client says */
1696         debugs(85, 3, "ENTRY_SPECIAL HIT " << *e);
1697         http->logType = LOG_TCP_HIT;
1698         doGetMoreData();
1699         return;
1700     }
1701
1702     if (r->flags.noCache) {
1703         debugs(85, 3, "no-cache REFRESH MISS " << *e);
1704         forgetHit();
1705         http->logType = LOG_TCP_CLIENT_REFRESH_MISS;
1706         doGetMoreData();
1707         return;
1708     }
1709
1710     debugs(85, 3, "default HIT " << *e);
1711     http->logType = LOG_TCP_HIT;
1712     doGetMoreData();
1713 }
1714
1715 /**
1716  * Request more data from the store for the client Stream
1717  * This is *the* entry point to this module.
1718  *
1719  * Preconditions:
1720  *  - This is the head of the list.
1721  *  - There is at least one more node.
1722  *  - Data context is not null
1723  */
1724 void
1725 clientGetMoreData(clientStreamNode * aNode, ClientHttpRequest * http)
1726 {
1727     /* Test preconditions */
1728     assert(aNode != NULL);
1729     assert(cbdataReferenceValid(aNode));
1730     assert(aNode->node.prev == NULL);
1731     assert(aNode->node.next != NULL);
1732     clientReplyContext *context = dynamic_cast<clientReplyContext *>(aNode->data.getRaw());
1733     assert (context);
1734     assert(context->http == http);
1735
1736     clientStreamNode *next = ( clientStreamNode *)aNode->node.next->data;
1737
1738     if (!context->ourNode)
1739         context->ourNode = aNode;
1740
1741     /* no cbdatareference, this is only used once, and safely */
1742     if (context->flags.storelogiccomplete) {
1743         StoreIOBuffer tempBuffer;
1744         tempBuffer.offset = next->readBuffer.offset + context->headers_sz;
1745         tempBuffer.length = next->readBuffer.length;
1746         tempBuffer.data = next->readBuffer.data;
1747
1748         storeClientCopy(context->sc, http->storeEntry(),
1749                         tempBuffer, clientReplyContext::SendMoreData, context);
1750         return;
1751     }
1752
1753     if (context->http->request->method == Http::METHOD_PURGE) {
1754         context->purgeRequest();
1755         return;
1756     }
1757
1758     // OPTIONS with Max-Forwards:0 handled in clientProcessRequest()
1759
1760     if (context->http->request->method == Http::METHOD_TRACE) {
1761         if (context->http->request->header.getInt64(Http::HdrType::MAX_FORWARDS) == 0) {
1762             context->traceReply(aNode);
1763             return;
1764         }
1765
1766         /* continue forwarding, not finished yet. */
1767         http->logType = LOG_TCP_MISS;
1768
1769         context->doGetMoreData();
1770     } else
1771         context->identifyStoreObject();
1772 }
1773
1774 void
1775 clientReplyContext::doGetMoreData()
1776 {
1777     /* We still have to do store logic processing - vary, cache hit etc */
1778     if (http->storeEntry() != NULL) {
1779         /* someone found the object in the cache for us */
1780         StoreIOBuffer localTempBuffer;
1781
1782         http->storeEntry()->lock("clientReplyContext::doGetMoreData");
1783
1784         MemObject *mem_obj = http->storeEntry()->makeMemObject();
1785         if (!mem_obj->hasUris()) {
1786             /*
1787              * This if-block exists because we don't want to clobber
1788              * a preexiting mem_obj->method value if the mem_obj
1789              * already exists.  For example, when a HEAD request
1790              * is a cache hit for a GET response, we want to keep
1791              * the method as GET.
1792              */
1793             mem_obj->setUris(storeId(), http->log_uri, http->request->method);
1794             /**
1795              * Here we can see if the object was
1796              * created using URL or alternative StoreID from helper.
1797              */
1798             debugs(88, 3, "storeId: " << http->storeEntry()->mem_obj->storeId());
1799         }
1800
1801         sc = storeClientListAdd(http->storeEntry(), this);
1802 #if USE_DELAY_POOLS
1803         sc->setDelayId(DelayId::DelayClient(http));
1804 #endif
1805
1806         assert(http->logType.oldType == LOG_TCP_HIT);
1807         reqofs = 0;
1808         /* guarantee nothing has been sent yet! */
1809         assert(http->out.size == 0);
1810         assert(http->out.offset == 0);
1811
1812         if (Ip::Qos::TheConfig.isHitTosActive()) {
1813             Ip::Qos::doTosLocalHit(http->getConn()->clientConnection);
1814         }
1815
1816         if (Ip::Qos::TheConfig.isHitNfmarkActive()) {
1817             Ip::Qos::doNfmarkLocalHit(http->getConn()->clientConnection);
1818         }
1819
1820         localTempBuffer.offset = reqofs;
1821         localTempBuffer.length = getNextNode()->readBuffer.length;
1822         localTempBuffer.data = getNextNode()->readBuffer.data;
1823         storeClientCopy(sc, http->storeEntry(), localTempBuffer, CacheHit, this);
1824     } else {
1825         /* MISS CASE, http->logType is already set! */
1826         processMiss();
1827     }
1828 }
1829
1830 /** The next node has removed itself from the stream. */
1831 void
1832 clientReplyDetach(clientStreamNode * node, ClientHttpRequest * http)
1833 {
1834     /** detach from the stream */
1835     clientStreamDetach(node, http);
1836 }
1837
1838 /**
1839  * Accepts chunk of a http message in buf, parses prefix, filters headers and
1840  * such, writes processed message to the message recipient
1841  */
1842 void
1843 clientReplyContext::SendMoreData(void *data, StoreIOBuffer result)
1844 {
1845     clientReplyContext *context = static_cast<clientReplyContext *>(data);
1846     context->sendMoreData (result);
1847 }
1848
1849 void
1850 clientReplyContext::makeThisHead()
1851 {
1852     /* At least, I think thats what this does */
1853     dlinkDelete(&http->active, &ClientActiveRequests);
1854     dlinkAdd(http, &http->active, &ClientActiveRequests);
1855 }
1856
1857 bool
1858 clientReplyContext::errorInStream(StoreIOBuffer const &result, size_t const &sizeToProcess)const
1859 {
1860     return /* aborted request */
1861         (http->storeEntry() && EBIT_TEST(http->storeEntry()->flags, ENTRY_ABORTED)) ||
1862         /* Upstream read error */ (result.flags.error) ||
1863         /* Upstream EOF */ (sizeToProcess == 0);
1864 }
1865
1866 void
1867 clientReplyContext::sendStreamError(StoreIOBuffer const &result)
1868 {
1869     /** call clientWriteComplete so the client socket gets closed
1870      *
1871      * We call into the stream, because we don't know that there is a
1872      * client socket!
1873      */
1874     debugs(88, 5, "clientReplyContext::sendStreamError: A stream error has occured, marking as complete and sending no data.");
1875     StoreIOBuffer localTempBuffer;
1876     flags.complete = 1;
1877     http->request->flags.streamError = true;
1878     localTempBuffer.flags.error = result.flags.error;
1879     clientStreamCallback((clientStreamNode*)http->client_stream.head->data, http, NULL,
1880                          localTempBuffer);
1881 }
1882
1883 void
1884 clientReplyContext::pushStreamData(StoreIOBuffer const &result, char *source)
1885 {
1886     StoreIOBuffer localTempBuffer;
1887
1888     if (result.length == 0) {
1889         debugs(88, 5, "clientReplyContext::pushStreamData: marking request as complete due to 0 length store result");
1890         flags.complete = 1;
1891     }
1892
1893     assert(result.offset - headers_sz == next()->readBuffer.offset);
1894     localTempBuffer.offset = result.offset - headers_sz;
1895     localTempBuffer.length = result.length;
1896
1897     if (localTempBuffer.length)
1898         localTempBuffer.data = source;
1899
1900     clientStreamCallback((clientStreamNode*)http->client_stream.head->data, http, NULL,
1901                          localTempBuffer);
1902 }
1903
1904 clientStreamNode *
1905 clientReplyContext::next() const
1906 {
1907     assert ( (clientStreamNode*)http->client_stream.head->next->data == getNextNode());
1908     return getNextNode();
1909 }
1910
1911 void
1912 clientReplyContext::sendBodyTooLargeError()
1913 {
1914     Ip::Address tmp_noaddr;
1915     tmp_noaddr.setNoAddr(); // TODO: make a global const
1916     http->logType = LOG_TCP_DENIED_REPLY;
1917     ErrorState *err = clientBuildError(ERR_TOO_BIG, Http::scForbidden, NULL,
1918                                        http->getConn() != NULL ? http->getConn()->clientConnection->remote : tmp_noaddr,
1919                                        http->request);
1920     removeClientStoreReference(&(sc), http);
1921     HTTPMSGUNLOCK(reply);
1922     startError(err);
1923
1924 }
1925
1926 /// send 412 (Precondition Failed) to client
1927 void
1928 clientReplyContext::sendPreconditionFailedError()
1929 {
1930     http->logType = LOG_TCP_HIT;
1931     ErrorState *const err =
1932         clientBuildError(ERR_PRECONDITION_FAILED, Http::scPreconditionFailed,
1933                          NULL, http->getConn()->clientConnection->remote, http->request);
1934     removeClientStoreReference(&sc, http);
1935     HTTPMSGUNLOCK(reply);
1936     startError(err);
1937 }
1938
1939 /// send 304 (Not Modified) to client
1940 void
1941 clientReplyContext::sendNotModified()
1942 {
1943     StoreEntry *e = http->storeEntry();
1944     const time_t timestamp = e->timestamp;
1945     HttpReply *const temprep = e->getReply()->make304();
1946     http->logType = LOG_TCP_IMS_HIT;
1947     removeClientStoreReference(&sc, http);
1948     createStoreEntry(http->request->method, RequestFlags());
1949     e = http->storeEntry();
1950     // Copy timestamp from the original entry so the 304
1951     // reply has a meaningful Age: header.
1952     e->timestampsSet();
1953     e->timestamp = timestamp;
1954     e->replaceHttpReply(temprep);
1955     e->complete();
1956     /*
1957      * TODO: why put this in the store and then serialise it and
1958      * then parse it again. Simply mark the request complete in
1959      * our context and write the reply struct to the client side.
1960      */
1961     triggerInitialStoreRead();
1962 }
1963
1964 /// send 304 (Not Modified) or 412 (Precondition Failed) to client
1965 /// depending on request method
1966 void
1967 clientReplyContext::sendNotModifiedOrPreconditionFailedError()
1968 {
1969     if (http->request->method == Http::METHOD_GET ||
1970             http->request->method == Http::METHOD_HEAD)
1971         sendNotModified();
1972     else
1973         sendPreconditionFailedError();
1974 }
1975
1976 void
1977 clientReplyContext::processReplyAccess ()
1978 {
1979     /* NP: this should probably soft-fail to a zero-sized-reply error ?? */
1980     assert(reply);
1981
1982     /** Don't block our own responses or HTTP status messages */
1983     if (http->logType.oldType == LOG_TCP_DENIED ||
1984             http->logType.oldType == LOG_TCP_DENIED_REPLY ||
1985             alwaysAllowResponse(reply->sline.status())) {
1986         headers_sz = reply->hdr_sz;
1987         processReplyAccessResult(ACCESS_ALLOWED);
1988         return;
1989     }
1990
1991     /** Check for reply to big error */
1992     if (reply->expectedBodyTooLarge(*http->request)) {
1993         sendBodyTooLargeError();
1994         return;
1995     }
1996
1997     headers_sz = reply->hdr_sz;
1998
1999     /** check for absent access controls (permit by default) */
2000     if (!Config.accessList.reply) {
2001         processReplyAccessResult(ACCESS_ALLOWED);
2002         return;
2003     }
2004
2005     /** Process http_reply_access lists */
2006     ACLFilledChecklist *replyChecklist =
2007         clientAclChecklistCreate(Config.accessList.reply, http);
2008     replyChecklist->reply = reply;
2009     HTTPMSGLOCK(replyChecklist->reply);
2010     replyChecklist->nonBlockingCheck(ProcessReplyAccessResult, this);
2011 }
2012
2013 void
2014 clientReplyContext::ProcessReplyAccessResult(allow_t rv, void *voidMe)
2015 {
2016     clientReplyContext *me = static_cast<clientReplyContext *>(voidMe);
2017     me->processReplyAccessResult(rv);
2018 }
2019
2020 void
2021 clientReplyContext::processReplyAccessResult(const allow_t &accessAllowed)
2022 {
2023     debugs(88, 2, "The reply for " << http->request->method
2024            << ' ' << http->uri << " is " << accessAllowed << ", because it matched "
2025            << (AclMatchedName ? AclMatchedName : "NO ACL's"));
2026
2027     if (accessAllowed != ACCESS_ALLOWED) {
2028         ErrorState *err;
2029         err_type page_id;
2030         page_id = aclGetDenyInfoPage(&Config.denyInfoList, AclMatchedName, 1);
2031
2032         http->logType = LOG_TCP_DENIED_REPLY;
2033
2034         if (page_id == ERR_NONE)
2035             page_id = ERR_ACCESS_DENIED;
2036
2037         Ip::Address tmp_noaddr;
2038         tmp_noaddr.setNoAddr();
2039         err = clientBuildError(page_id, Http::scForbidden, NULL,
2040                                http->getConn() != NULL ? http->getConn()->clientConnection->remote : tmp_noaddr,
2041                                http->request);
2042
2043         removeClientStoreReference(&sc, http);
2044
2045         HTTPMSGUNLOCK(reply);
2046
2047         startError(err);
2048
2049         return;
2050     }
2051
2052     /* Ok, the reply is allowed, */
2053     http->loggingEntry(http->storeEntry());
2054
2055     ssize_t body_size = reqofs - reply->hdr_sz;
2056     if (body_size < 0) {
2057         reqofs = reply->hdr_sz;
2058         body_size = 0;
2059     }
2060
2061     debugs(88, 3, "clientReplyContext::sendMoreData: Appending " <<
2062            (int) body_size << " bytes after " << reply->hdr_sz <<
2063            " bytes of headers");
2064
2065 #if USE_SQUID_ESI
2066
2067     if (http->flags.accel && reply->sline.status() != Http::scForbidden &&
2068             !alwaysAllowResponse(reply->sline.status()) &&
2069             esiEnableProcessing(reply)) {
2070         debugs(88, 2, "Enabling ESI processing for " << http->uri);
2071         clientStreamInsertHead(&http->client_stream, esiStreamRead,
2072                                esiProcessStream, esiStreamDetach, esiStreamStatus, NULL);
2073     }
2074
2075 #endif
2076
2077     if (http->request->method == Http::METHOD_HEAD) {
2078         /* do not forward body for HEAD replies */
2079         body_size = 0;
2080         http->flags.done_copying = true;
2081         flags.complete = 1;
2082     }
2083
2084     assert (!flags.headersSent);
2085     flags.headersSent = true;
2086
2087     StoreIOBuffer localTempBuffer;
2088     char *buf = next()->readBuffer.data;
2089     char *body_buf = buf + reply->hdr_sz;
2090
2091     //Server side may disable ranges under some circumstances.
2092
2093     if ((!http->request->range))
2094         next()->readBuffer.offset = 0;
2095
2096     body_buf -= next()->readBuffer.offset;
2097
2098     if (next()->readBuffer.offset != 0) {
2099         if (next()->readBuffer.offset > body_size) {
2100             /* Can't use any of the body we received. send nothing */
2101             localTempBuffer.length = 0;
2102             localTempBuffer.data = NULL;
2103         } else {
2104             localTempBuffer.length = body_size - next()->readBuffer.offset;
2105             localTempBuffer.data = body_buf + next()->readBuffer.offset;
2106         }
2107     } else {
2108         localTempBuffer.length = body_size;
2109         localTempBuffer.data = body_buf;
2110     }
2111
2112     /* TODO??: move the data in the buffer back by the request header size */
2113     clientStreamCallback((clientStreamNode *)http->client_stream.head->data,
2114                          http, reply, localTempBuffer);
2115
2116     return;
2117 }
2118
2119 void
2120 clientReplyContext::sendMoreData (StoreIOBuffer result)
2121 {
2122     if (deleting)
2123         return;
2124
2125     StoreEntry *entry = http->storeEntry();
2126
2127     ConnStateData * conn = http->getConn();
2128
2129     // too late, our conn is closing
2130     // TODO: should we also quit?
2131     if (conn == NULL) {
2132         debugs(33,3, "not sending more data to a closed connection" );
2133         return;
2134     }
2135     if (!conn->isOpen()) {
2136         debugs(33,3, "not sending more data to closing connection " << conn->clientConnection);
2137         return;
2138     }
2139     if (conn->pinning.zeroReply) {
2140         debugs(33,3, "not sending more data after a pinned zero reply " << conn->clientConnection);
2141         return;
2142     }
2143
2144     char *buf = next()->readBuffer.data;
2145
2146     if (buf != result.data) {
2147         /* we've got to copy some data */
2148         assert(result.length <= next()->readBuffer.length);
2149         memcpy(buf, result.data, result.length);
2150     }
2151
2152     if (reqofs==0 && !http->logType.isTcpHit() && Comm::IsConnOpen(conn->clientConnection)) {
2153         if (Ip::Qos::TheConfig.isHitTosActive()) {
2154             Ip::Qos::doTosLocalMiss(conn->clientConnection, http->request->hier.code);
2155         }
2156         if (Ip::Qos::TheConfig.isHitNfmarkActive()) {
2157             Ip::Qos::doNfmarkLocalMiss(conn->clientConnection, http->request->hier.code);
2158         }
2159     }
2160
2161     /* We've got the final data to start pushing... */
2162     flags.storelogiccomplete = 1;
2163
2164     reqofs += result.length;
2165
2166     assert(reqofs <= HTTP_REQBUF_SZ || flags.headersSent);
2167
2168     assert(http->request != NULL);
2169
2170     /* ESI TODO: remove this assert once everything is stable */
2171     assert(http->client_stream.head->data
2172            && cbdataReferenceValid(http->client_stream.head->data));
2173
2174     makeThisHead();
2175
2176     debugs(88, 5, "clientReplyContext::sendMoreData: " << http->uri << ", " <<
2177            reqofs << " bytes (" << result.length <<
2178            " new bytes)");
2179     debugs(88, 5, "clientReplyContext::sendMoreData:"
2180            << conn->clientConnection <<
2181            " '" << entry->url() << "'" <<
2182            " out.offset=" << http->out.offset);
2183
2184     /* update size of the request */
2185     reqsize = reqofs;
2186
2187     if (errorInStream(result, reqofs)) {
2188         sendStreamError(result);
2189         return;
2190     }
2191
2192     if (flags.headersSent) {
2193         pushStreamData (result, buf);
2194         return;
2195     }
2196
2197     cloneReply();
2198
2199     /* handle headers */
2200
2201     if (Config.onoff.log_mime_hdrs) {
2202         size_t k;
2203
2204         if ((k = headersEnd(buf, reqofs))) {
2205             safe_free(http->al->headers.reply);
2206             http->al->headers.reply = (char *)xcalloc(k + 1, 1);
2207             xstrncpy(http->al->headers.reply, buf, k);
2208         }
2209     }
2210
2211     holdingBuffer = result;
2212     processReplyAccess();
2213     return;
2214 }
2215
2216 /* Using this breaks the client layering just a little!
2217  */
2218 void
2219 clientReplyContext::createStoreEntry(const HttpRequestMethod& m, RequestFlags reqFlags)
2220 {
2221     assert(http != NULL);
2222     /*
2223      * For erroneous requests, we might not have a h->request,
2224      * so make a fake one.
2225      */
2226
2227     if (http->request == NULL) {
2228         http->request = new HttpRequest(m, AnyP::PROTO_NONE, null_string);
2229         HTTPMSGLOCK(http->request);
2230     }
2231
2232     StoreEntry *e = storeCreateEntry(storeId(), http->log_uri, reqFlags, m);
2233
2234     // Make entry collapsable ASAP, to increase collapsing chances for others,
2235     // TODO: every must-revalidate and similar request MUST reach the origin,
2236     // but do we have to prohibit others from collapsing on that request?
2237     if (Config.onoff.collapsed_forwarding && reqFlags.cachable &&
2238             !reqFlags.needValidation &&
2239             (m == Http::METHOD_GET || m == Http::METHOD_HEAD)) {
2240         // make the entry available for future requests now
2241         Store::Root().allowCollapsing(e, reqFlags, m);
2242     }
2243
2244     sc = storeClientListAdd(e, this);
2245
2246 #if USE_DELAY_POOLS
2247     sc->setDelayId(DelayId::DelayClient(http));
2248 #endif
2249
2250     reqofs = 0;
2251
2252     reqsize = 0;
2253
2254     /* I don't think this is actually needed! -- adrian */
2255     /* http->reqbuf = http->norm_reqbuf; */
2256     //    assert(http->reqbuf == http->norm_reqbuf);
2257     /* The next line is illegal because we don't know if the client stream
2258      * buffers have been set up
2259      */
2260     //    storeClientCopy(http->sc, e, 0, HTTP_REQBUF_SZ, http->reqbuf,
2261     //        SendMoreData, this);
2262     /* So, we mark the store logic as complete */
2263     flags.storelogiccomplete = 1;
2264
2265     /* and get the caller to request a read, from whereever they are */
2266     /* NOTE: after ANY data flows down the pipe, even one step,
2267      * this function CAN NOT be used to manage errors
2268      */
2269     http->storeEntry(e);
2270 }
2271
2272 ErrorState *
2273 clientBuildError(err_type page_id, Http::StatusCode status, char const *url,
2274                  Ip::Address &src_addr, HttpRequest * request)
2275 {
2276     ErrorState *err = new ErrorState(page_id, status, request);
2277     err->src_addr = src_addr;
2278
2279     if (url)
2280         err->url = xstrdup(url);
2281
2282     return err;
2283 }
2284