src/errorpage.cc

   1 /*
   2  * DEBUG: section 04    Error Generation
   3  * AUTHOR: Duane Wessels
   4  *
   5  * SQUID Web Proxy Cache          http://www.squid-cache.org/
   6  * ----------------------------------------------------------
   7  *
   8  *  Squid is the result of efforts by numerous individuals from
   9  *  the Internet community; see the CONTRIBUTORS file for full
  10  *  details.   Many organizations have provided support for Squid's
  11  *  development; see the SPONSORS file for full details.  Squid is
  12  *  Copyrighted (C) 2001 by the Regents of the University of
  13  *  California; see the COPYRIGHT file for full details.  Squid
  14  *  incorporates software developed and/or copyrighted by other
  15  *  sources; see the CREDITS file for full details.
  16  *
  17  *  This program is free software; you can redistribute it and/or modify
  18  *  it under the terms of the GNU General Public License as published by
  19  *  the Free Software Foundation; either version 2 of the License, or
  20  *  (at your option) any later version.
  21  *
  22  *  This program is distributed in the hope that it will be useful,
  23  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  24  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  25  *  GNU General Public License for more details.
  26  *
  27  *  You should have received a copy of the GNU General Public License
  28  *  along with this program; if not, write to the Free Software
  29  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
  30  *
  31  */
  32 #include "squid.h"
  33 #include "cache_cf.h"
  34 #include "clients/forward.h"
  35 #include "comm/Connection.h"
  36 #include "comm/Write.h"
  37 #include "disk.h"
  38 #include "err_detail_type.h"
  39 #include "errorpage.h"
  40 #include "fde.h"
  41 #include "html_quote.h"
  42 #include "HttpHeaderTools.h"
  43 #include "HttpReply.h"
  44 #include "HttpRequest.h"
  45 #include "MemBuf.h"
  46 #include "MemObject.h"
  47 #include "rfc1738.h"
  48 #include "SquidConfig.h"
  49 #include "Store.h"
  50 #include "tools.h"
  51 #include "URL.h"
  52 #include "wordlist.h"
  53 #if USE_AUTH
  54 #include "auth/UserRequest.h"
  55 #endif
  56 #include "SquidTime.h"
  57 #if USE_OPENSSL
  58 #include "ssl/ErrorDetailManager.h"
  59 #endif
  60
  61 /**
  62  \defgroup ErrorPageInternal Error Page Internals
  63  \ingroup ErrorPageAPI
  64  *
  65  \section Abstract Abstract:
  66  *   These routines are used to generate error messages to be
  67  *   sent to clients.  The error type is used to select between
  68  *   the various message formats. (formats are stored in the
  69  *   Config.errorDirectory)
  70  */
  71
  72 #if !defined(DEFAULT_SQUID_ERROR_DIR)
  73 /** Where to look for errors if config path fails.
  74  \note Please use ./configure --datadir=/path instead of patching
  75  */
  76 #define DEFAULT_SQUID_ERROR_DIR   DEFAULT_SQUID_DATA_DIR"/errors"
  77 #endif
  78
  79 /// \ingroup ErrorPageInternal
  80 CBDATA_CLASS_INIT(ErrorState);
  81
  82 /* local types */
  83
  84 /// \ingroup ErrorPageInternal
  85 typedef struct {
  86     int id;
  87     char *page_name;
  88     Http::StatusCode page_redirect;
  89 } ErrorDynamicPageInfo;
  90
  91 /* local constant and vars */
  92
  93 /**
  94  \ingroup ErrorPageInternal
  95  *
  96  \note  hard coded error messages are not appended with %S
  97  *      automagically to give you more control on the format
  98  */
  99 static const struct {
 100     int type;                   /* and page_id */
 101     const char *text;
 102 }
 103
 104 error_hard_text[] = {
 105
 106     {
 107         ERR_SQUID_SIGNATURE,
 108         "\n<br>\n"
 109         "<hr>\n"
 110         "<div id=\"footer\">\n"
 111         "Generated %T by %h (%s)\n"
 112         "</div>\n"
 113         "</body></html>\n"
 114     },
 115     {
 116         TCP_RESET,
 117         "reset"
 118     }
 119 };
 120
 121 /// \ingroup ErrorPageInternal
 122 static std::vector<ErrorDynamicPageInfo *> ErrorDynamicPages;
 123
 124 /* local prototypes */
 125
 126 /// \ingroup ErrorPageInternal
 127 static const int error_hard_text_count = sizeof(error_hard_text) / sizeof(*error_hard_text);
 128
 129 /// \ingroup ErrorPageInternal
 130 static char **error_text = NULL;
 131
 132 /// \ingroup ErrorPageInternal
 133 static int error_page_count = 0;
 134
 135 /// \ingroup ErrorPageInternal
 136 static MemBuf error_stylesheet;
 137
 138 static const char *errorFindHardText(err_type type);
 139 static ErrorDynamicPageInfo *errorDynamicPageInfoCreate(int id, const char *page_name);
 140 static void errorDynamicPageInfoDestroy(ErrorDynamicPageInfo * info);
 141 static IOCB errorSendComplete;
 142
 143 /// \ingroup ErrorPageInternal
 144 /// manages an error page template
 145 class ErrorPageFile: public TemplateFile
 146 {
 147 public:
 148     ErrorPageFile(const char *name, const err_type code): TemplateFile(name,code) { textBuf.init();}
 149
 150     /// The template text data read from disk
 151     const char *text() { return textBuf.content(); }
 152
 153 private:
 154     /// stores the data read from disk to a local buffer
 155     virtual bool parse(const char *buf, int len, bool eof) {
 156         if (len)
 157             textBuf.append(buf, len);
 158         return true;
 159     }
 160
 161     MemBuf textBuf; ///< A buffer to store the error page
 162 };
 163
 164 /// \ingroup ErrorPageInternal
 165 err_type &operator++ (err_type &anErr)
 166 {
 167     int tmp = (int)anErr;
 168     anErr = (err_type)(++tmp);
 169     return anErr;
 170 }
 171
 172 /// \ingroup ErrorPageInternal
 173 int operator - (err_type const &anErr, err_type const &anErr2)
 174 {
 175     return (int)anErr - (int)anErr2;
 176 }
 177
 178 void
 179 errorInitialize(void)
 180 {
 181     err_type i;
 182     const char *text;
 183     error_page_count = ERR_MAX + ErrorDynamicPages.size();
 184     error_text = static_cast<char **>(xcalloc(error_page_count, sizeof(char *)));
 185
 186     for (i = ERR_NONE, ++i; i < error_page_count; ++i) {
 187         safe_free(error_text[i]);
 188
 189         if ((text = errorFindHardText(i))) {
 190             /**\par
 191              * Index any hard-coded error text into defaults.
 192              */
 193             error_text[i] = xstrdup(text);
 194
 195         } else if (i < ERR_MAX) {
 196             /**\par
 197              * Index precompiled fixed template files from one of two sources:
 198              *  (a) default language translation directory (error_default_language)
 199              *  (b) admin specified custom directory (error_directory)
 200              */
 201             ErrorPageFile errTmpl(err_type_str[i], i);
 202             error_text[i] = errTmpl.loadDefault() ? xstrdup(errTmpl.text()) : NULL;
 203         } else {
 204             /** \par
 205              * Index any unknown file names used by deny_info.
 206              */
 207             ErrorDynamicPageInfo *info = ErrorDynamicPages.at(i - ERR_MAX);
 208             assert(info && info->id == i && info->page_name);
 209
 210             const char *pg = info->page_name;
 211             if (info->page_redirect != Http::scNone)
 212                 pg = info->page_name +4;
 213
 214             if (strchr(pg, ':') == NULL) {
 215                 /** But only if they are not redirection URL. */
 216                 ErrorPageFile errTmpl(pg, ERR_MAX);
 217                 error_text[i] = errTmpl.loadDefault() ? xstrdup(errTmpl.text()) : NULL;
 218             }
 219         }
 220     }
 221
 222     error_stylesheet.reset();
 223
 224     // look for and load stylesheet into global MemBuf for it.
 225     if (Config.errorStylesheet) {
 226         ErrorPageFile tmpl("StylesSheet", ERR_MAX);
 227         tmpl.loadFromFile(Config.errorStylesheet);
 228         error_stylesheet.Printf("%s",tmpl.text());
 229     }
 230
 231 #if USE_OPENSSL
 232     Ssl::errorDetailInitialize();
 233 #endif
 234 }
 235
 236 void
 237 errorClean(void)
 238 {
 239     if (error_text) {
 240         int i;
 241
 242         for (i = ERR_NONE + 1; i < error_page_count; ++i)
 243             safe_free(error_text[i]);
 244
 245         safe_free(error_text);
 246     }
 247
 248     while (!ErrorDynamicPages.empty()) {
 249         errorDynamicPageInfoDestroy(ErrorDynamicPages.back());
 250         ErrorDynamicPages.pop_back();
 251     }
 252
 253     error_page_count = 0;
 254
 255 #if USE_OPENSSL
 256     Ssl::errorDetailClean();
 257 #endif
 258 }
 259
 260 /// \ingroup ErrorPageInternal
 261 static const char *
 262 errorFindHardText(err_type type)
 263 {
 264     int i;
 265
 266     for (i = 0; i < error_hard_text_count; ++i)
 267         if (error_hard_text[i].type == type)
 268             return error_hard_text[i].text;
 269
 270     return NULL;
 271 }
 272
 273 TemplateFile::TemplateFile(const char *name, const err_type code): silent(false), wasLoaded(false), templateName(name), templateCode(code)
 274 {
 275     assert(name);
 276 }
 277
 278 bool
 279 TemplateFile::loadDefault()
 280 {
 281     if (loaded()) // already loaded?
 282         return true;
 283
 284     /** test error_directory configured location */
 285     if (Config.errorDirectory) {
 286         char path[MAXPATHLEN];
 287         snprintf(path, sizeof(path), "%s/%s", Config.errorDirectory, templateName.termedBuf());
 288         loadFromFile(path);
 289     }
 290
 291 #if USE_ERR_LOCALES
 292     /** test error_default_language location */
 293     if (!loaded() && Config.errorDefaultLanguage) {
 294         if (!tryLoadTemplate(Config.errorDefaultLanguage)) {
 295             debugs(1, (templateCode < TCP_RESET ? DBG_CRITICAL : 3), "Unable to load default error language files. Reset to backups.");
 296         }
 297     }
 298 #endif
 299
 300     /* test default location if failed (templates == English translation base templates) */
 301     if (!loaded()) {
 302         tryLoadTemplate("templates");
 303     }
 304
 305     /* giving up if failed */
 306     if (!loaded()) {
 307         debugs(1, (templateCode < TCP_RESET ? DBG_CRITICAL : 3), "WARNING: failed to find or read error text file " << templateName);
 308         parse("Internal Error: Missing Template ", 33, '\0');
 309         parse(templateName.termedBuf(), templateName.size(), '\0');
 310     }
 311
 312     return true;
 313 }
 314
 315 bool
 316 TemplateFile::tryLoadTemplate(const char *lang)
 317 {
 318     assert(lang);
 319
 320     char path[MAXPATHLEN];
 321     /* TODO: prep the directory path string to prevent snprintf ... */
 322     snprintf(path, sizeof(path), "%s/%s/%s",
 323              DEFAULT_SQUID_ERROR_DIR, lang, templateName.termedBuf());
 324     path[MAXPATHLEN-1] = '\0';
 325
 326     if (loadFromFile(path))
 327         return true;
 328
 329 #if HAVE_GLOB
 330     if ( strlen(lang) == 2) {
 331         /* TODO glob the error directory for sub-dirs matching: <tag> '-*'   */
 332         /* use first result. */
 333         debugs(4,2, HERE << "wildcard fallback errors not coded yet.");
 334     }
 335 #endif
 336
 337     return false;
 338 }
 339
 340 bool
 341 TemplateFile::loadFromFile(const char *path)
 342 {
 343     int fd;
 344     char buf[4096];
 345     ssize_t len;
 346
 347     if (loaded()) // already loaded?
 348         return true;
 349
 350     fd = file_open(path, O_RDONLY | O_TEXT);
 351
 352     if (fd < 0) {
 353         /* with dynamic locale negotiation we may see some failures before a success. */
 354         if (!silent && templateCode < TCP_RESET)
 355             debugs(4, DBG_CRITICAL, HERE << "'" << path << "': " << xstrerror());
 356         wasLoaded = false;
 357         return wasLoaded;
 358     }
 359
 360     while ((len = FD_READ_METHOD(fd, buf, sizeof(buf))) > 0) {
 361         if (!parse(buf, len, false)) {
 362             debugs(4, DBG_CRITICAL, HERE << " parse error while reading template file: " << path);
 363             wasLoaded = false;
 364             return wasLoaded;
 365         }
 366     }
 367     parse(buf, 0, true);
 368
 369     if (len < 0) {
 370         debugs(4, DBG_CRITICAL, HERE << "failed to fully read: '" << path << "': " << xstrerror());
 371     }
 372
 373     file_close(fd);
 374
 375     wasLoaded = true;
 376     return wasLoaded;
 377 }
 378
 379 bool strHdrAcptLangGetItem(const String &hdr, char *lang, int langLen, size_t &pos)
 380 {
 381     while (pos < hdr.size()) {
 382         char *dt = lang;
 383
 384         /* skip any initial whitespace. */
 385         while (pos < hdr.size() && xisspace(hdr[pos]))
 386             ++pos;
 387
 388         /*
 389          * Header value format:
 390          *  - sequence of whitespace delimited tags
 391          *  - each tag may suffix with ';'.* which we can ignore.
 392          *  - IFF a tag contains only two characters we can wildcard ANY translations matching: <it> '-'? .*
 393          *    with preference given to an exact match.
 394          */
 395         bool invalid_byte = false;
 396         while (pos < hdr.size() && hdr[pos] != ';' && hdr[pos] != ',' && !xisspace(hdr[pos]) && dt < (lang + (langLen -1)) ) {
 397             if (!invalid_byte) {
 398 #if USE_HTTP_VIOLATIONS
 399                 // if accepting violations we may as well accept some broken browsers
 400                 //  which may send us the right code, wrong ISO formatting.
 401                 if (hdr[pos] == '_')
 402                     *dt = '-';
 403                 else
 404 #endif
 405                     *dt = xtolower(hdr[pos]);
 406                 // valid codes only contain A-Z, hyphen (-) and *
 407                 if (*dt != '-' && *dt != '*' && (*dt < 'a' || *dt > 'z') )
 408                     invalid_byte = true;
 409                 else
 410                     ++dt; // move to next destination byte.
 411             }
 412             ++pos;
 413         }
 414         *dt = '\0'; // nul-terminated the filename content string before system use.
 415         ++dt;
 416
 417         // if we terminated the tag on garbage or ';' we need to skip to the next ',' or end of header.
 418         while (pos < hdr.size() && hdr[pos] != ',')
 419             ++pos;
 420
 421         if (pos < hdr.size() && hdr[pos] == ',')
 422             ++pos;
 423
 424         debugs(4, 9, HERE << "STATE: dt='" << dt << "', lang='" << lang << "', pos=" << pos << ", buf='" << ((pos < hdr.size()) ? hdr.substr(pos,hdr.size()) : "") << "'");
 425
 426         /* if we found anything we might use, try it. */
 427         if (*lang != '\0' && !invalid_byte)
 428             return true;
 429     }
 430     return false;
 431 }
 432
 433 bool
 434 TemplateFile::loadFor(const HttpRequest *request)
 435 {
 436     String hdr;
 437
 438 #if USE_ERR_LOCALES
 439     if (loaded()) // already loaded?
 440         return true;
 441
 442     if (!request || !request->header.getList(HDR_ACCEPT_LANGUAGE, &hdr) )
 443         return false;
 444
 445     char lang[256];
 446     size_t pos = 0; // current parsing position in header string
 447
 448     debugs(4, 6, HERE << "Testing Header: '" << hdr << "'");
 449
 450     while ( strHdrAcptLangGetItem(hdr, lang, 256, pos) ) {
 451
 452         /* wildcard uses the configured default language */
 453         if (lang[0] == '*' && lang[1] == '\0') {
 454             debugs(4, 6, HERE << "Found language '" << lang << "'. Using configured default.");
 455             return false;
 456         }
 457
 458         debugs(4, 6, HERE << "Found language '" << lang << "', testing for available template");
 459
 460         if (tryLoadTemplate(lang)) {
 461             /* store the language we found for the Content-Language reply header */
 462             errLanguage = lang;
 463             break;
 464         } else if (Config.errorLogMissingLanguages) {
 465             debugs(4, DBG_IMPORTANT, "WARNING: Error Pages Missing Language: " << lang);
 466         }
 467     }
 468 #endif
 469
 470     return loaded();
 471 }
 472
 473 /// \ingroup ErrorPageInternal
 474 static ErrorDynamicPageInfo *
 475 errorDynamicPageInfoCreate(int id, const char *page_name)
 476 {
 477     ErrorDynamicPageInfo *info = new ErrorDynamicPageInfo;
 478     info->id = id;
 479     info->page_name = xstrdup(page_name);
 480     info->page_redirect = static_cast<Http::StatusCode>(atoi(page_name));
 481
 482     /* WARNING on redirection status:
 483      * 2xx are permitted, but not documented officially.
 484      * - might be useful for serving static files (PAC etc) in special cases
 485      * 3xx require a URL suitable for Location: header.
 486      * - the current design does not allow for a Location: URI as well as a local file template
 487      *   although this possibility is explicitly permitted in the specs.
 488      * 4xx-5xx require a local file template.
 489      * - sending Location: on these codes with no body is invalid by the specs.
 490      * - current result is Squid crashing or XSS problems as dynamic deny_info load random disk files.
 491      * - a future redesign of the file loading may result in loading remote objects sent inline as local body.
 492      */
 493     if (info->page_redirect == Http::scNone)
 494         ; // special case okay.
 495     else if (info->page_redirect < 200 || info->page_redirect > 599) {
 496         // out of range
 497         debugs(0, DBG_CRITICAL, "FATAL: status " << info->page_redirect << " is not valid on '" << page_name << "'");
 498         self_destruct();
 499     } else if ( /* >= 200 && */ info->page_redirect < 300 && strchr(&(page_name[4]), ':')) {
 500         // 2xx require a local template file
 501         debugs(0, DBG_CRITICAL, "FATAL: status " << info->page_redirect << " requires a template on '" << page_name << "'");
 502         self_destruct();
 503     } else if (info->page_redirect >= 300 && info->page_redirect <= 399 && !strchr(&(page_name[4]), ':')) {
 504         // 3xx require an absolute URL
 505         debugs(0, DBG_CRITICAL, "FATAL: status " << info->page_redirect << " requires a URL on '" << page_name << "'");
 506         self_destruct();
 507     } else if (info->page_redirect >= 400 /* && <= 599 */ && strchr(&(page_name[4]), ':')) {
 508         // 4xx/5xx require a local template file
 509         debugs(0, DBG_CRITICAL, "FATAL: status " << info->page_redirect << " requires a template on '" << page_name << "'");
 510         self_destruct();
 511     }
 512     // else okay.
 513
 514     return info;
 515 }
 516
 517 /// \ingroup ErrorPageInternal
 518 static void
 519 errorDynamicPageInfoDestroy(ErrorDynamicPageInfo * info)
 520 {
 521     assert(info);
 522     safe_free(info->page_name);
 523     delete info;
 524 }
 525
 526 /// \ingroup ErrorPageInternal
 527 static int
 528 errorPageId(const char *page_name)
 529 {
 530     for (int i = 0; i < ERR_MAX; ++i) {
 531         if (strcmp(err_type_str[i], page_name) == 0)
 532             return i;
 533     }
 534
 535     for (size_t j = 0; j < ErrorDynamicPages.size(); ++j) {
 536         if (strcmp(ErrorDynamicPages[j]->page_name, page_name) == 0)
 537             return j + ERR_MAX;
 538     }
 539
 540     return ERR_NONE;
 541 }
 542
 543 err_type
 544 errorReservePageId(const char *page_name)
 545 {
 546     ErrorDynamicPageInfo *info;
 547     int id = errorPageId(page_name);
 548
 549     if (id == ERR_NONE) {
 550         info = errorDynamicPageInfoCreate(ERR_MAX + ErrorDynamicPages.size(), page_name);
 551         ErrorDynamicPages.push_back(info);
 552         id = info->id;
 553     }
 554
 555     return (err_type)id;
 556 }
 557
 558 /// \ingroup ErrorPageInternal
 559 const char *
 560 errorPageName(int pageId)
 561 {
 562     if (pageId >= ERR_NONE && pageId < ERR_MAX)         /* common case */
 563         return err_type_str[pageId];
 564
 565     if (pageId >= ERR_MAX && pageId - ERR_MAX < (ssize_t)ErrorDynamicPages.size())
 566         return ErrorDynamicPages[pageId - ERR_MAX]->page_name;
 567
 568     return "ERR_UNKNOWN";       /* should not happen */
 569 }
 570
 571 ErrorState *
 572 ErrorState::NewForwarding(err_type type, HttpRequest *request)
 573 {
 574     assert(request);
 575     const Http::StatusCode status = request->flags.needValidation ?
 576                                     Http::scGatewayTimeout : Http::scServiceUnavailable;
 577     return new ErrorState(type, status, request);
 578 }
 579
 580 ErrorState::ErrorState(err_type t, Http::StatusCode status, HttpRequest * req) :
 581         type(t),
 582         page_id(t),
 583         err_language(NULL),
 584         httpStatus(status),
 585 #if USE_AUTH
 586         auth_user_request (NULL),
 587 #endif
 588         request(NULL),
 589         url(NULL),
 590         xerrno(0),
 591         port(0),
 592         dnsError(),
 593         ttl(0),
 594         src_addr(),
 595         redirect_url(NULL),
 596         callback(NULL),
 597         callback_data(NULL),
 598         request_hdrs(NULL),
 599         err_msg(NULL),
 600 #if USE_OPENSSL
 601         detail(NULL),
 602 #endif
 603         detailCode(ERR_DETAIL_NONE)
 604 {
 605     memset(&ftp, 0, sizeof(ftp));
 606
 607     if (page_id >= ERR_MAX && ErrorDynamicPages[page_id - ERR_MAX]->page_redirect != Http::scNone)
 608         httpStatus = ErrorDynamicPages[page_id - ERR_MAX]->page_redirect;
 609
 610     if (req != NULL) {
 611         request = req;
 612         HTTPMSGLOCK(request);
 613         src_addr = req->client_addr;
 614     }
 615 }
 616
 617 void
 618 errorAppendEntry(StoreEntry * entry, ErrorState * err)
 619 {
 620     assert(entry->mem_obj != NULL);
 621     assert (entry->isEmpty());
 622     debugs(4, 4, "Creating an error page for entry " << entry <<
 623            " with errorstate " << err <<
 624            " page id " << err->page_id);
 625
 626     if (entry->store_status != STORE_PENDING) {
 627         debugs(4, 2, "Skipping error page due to store_status: " << entry->store_status);
 628         /*
 629          * If the entry is not STORE_PENDING, then no clients
 630          * care about it, and we don't need to generate an
 631          * error message
 632          */
 633         assert(EBIT_TEST(entry->flags, ENTRY_ABORTED));
 634         assert(entry->mem_obj->nclients == 0);
 635         delete err;
 636         return;
 637     }
 638
 639     if (err->page_id == TCP_RESET) {
 640         if (err->request) {
 641             debugs(4, 2, "RSTing this reply");
 642             err->request->flags.resetTcp = true;
 643         }
 644     }
 645
 646     entry->lock("errorAppendEntry");
 647     entry->buffer();
 648     entry->replaceHttpReply( err->BuildHttpReply() );
 649     entry->flush();
 650     entry->complete();
 651     entry->negativeCache();
 652     entry->releaseRequest();
 653     entry->unlock("errorAppendEntry");
 654     delete err;
 655 }
 656
 657 void
 658 errorSend(const Comm::ConnectionPointer &conn, ErrorState * err)
 659 {
 660     HttpReply *rep;
 661     debugs(4, 3, HERE << conn << ", err=" << err);
 662     assert(Comm::IsConnOpen(conn));
 663
 664     rep = err->BuildHttpReply();
 665
 666     MemBuf *mb = rep->pack();
 667     AsyncCall::Pointer call = commCbCall(78, 5, "errorSendComplete",
 668                                          CommIoCbPtrFun(&errorSendComplete, err));
 669     Comm::Write(conn, mb, call);
 670     delete mb;
 671
 672     delete rep;
 673 }
 674
 675 /**
 676  \ingroup ErrorPageAPI
 677  *
 678  * Called by commHandleWrite() after data has been written
 679  * to the client socket.
 680  *
 681  \note If there is a callback, the callback is responsible for
 682  *     closing the FD, otherwise we do it ourselves.
 683  */
 684 static void
 685 errorSendComplete(const Comm::ConnectionPointer &conn, char *bufnotused, size_t size, Comm::Flag errflag, int xerrno, void *data)
 686 {
 687     ErrorState *err = static_cast<ErrorState *>(data);
 688     debugs(4, 3, HERE << conn << ", size=" << size);
 689
 690     if (errflag != Comm::ERR_CLOSING) {
 691         if (err->callback) {
 692             debugs(4, 3, "errorSendComplete: callback");
 693             err->callback(conn->fd, err->callback_data, size);
 694         } else {
 695             debugs(4, 3, "errorSendComplete: comm_close");
 696             conn->close();
 697         }
 698     }
 699
 700     delete err;
 701 }
 702
 703 ErrorState::~ErrorState()
 704 {
 705     HTTPMSGUNLOCK(request);
 706     safe_free(redirect_url);
 707     safe_free(url);
 708     safe_free(request_hdrs);
 709     wordlistDestroy(&ftp.server_msg);
 710     safe_free(ftp.request);
 711     safe_free(ftp.reply);
 712 #if USE_AUTH
 713     auth_user_request = NULL;
 714 #endif
 715     safe_free(err_msg);
 716 #if USE_ERR_LOCALES
 717     if (err_language != Config.errorDefaultLanguage)
 718 #endif
 719         safe_free(err_language);
 720 #if USE_OPENSSL
 721     delete detail;
 722 #endif
 723 }
 724
 725 int
 726 ErrorState::Dump(MemBuf * mb)
 727 {
 728     MemBuf str;
 729     char ntoabuf[MAX_IPSTRLEN];
 730
 731     str.reset();
 732     /* email subject line */
 733     str.Printf("CacheErrorInfo - %s", errorPageName(type));
 734     mb->Printf("?subject=%s", rfc1738_escape_part(str.buf));
 735     str.reset();
 736     /* email body */
 737     str.Printf("CacheHost: %s\r\n", getMyHostname());
 738     /* - Err Msgs */
 739     str.Printf("ErrPage: %s\r\n", errorPageName(type));
 740
 741     if (xerrno) {
 742         str.Printf("Err: (%d) %s\r\n", xerrno, strerror(xerrno));
 743     } else {
 744         str.Printf("Err: [none]\r\n");
 745     }
 746 #if USE_AUTH
 747     if (auth_user_request->denyMessage())
 748         str.Printf("Auth ErrMsg: %s\r\n", auth_user_request->denyMessage());
 749 #endif
 750     if (dnsError.size() > 0)
 751         str.Printf("DNS ErrMsg: %s\r\n", dnsError.termedBuf());
 752
 753     /* - TimeStamp */
 754     str.Printf("TimeStamp: %s\r\n\r\n", mkrfc1123(squid_curtime));
 755
 756     /* - IP stuff */
 757     str.Printf("ClientIP: %s\r\n", src_addr.toStr(ntoabuf,MAX_IPSTRLEN));
 758
 759     if (request && request->hier.host[0] != '\0') {
 760         str.Printf("ServerIP: %s\r\n", request->hier.host);
 761     }
 762
 763     str.Printf("\r\n");
 764     /* - HTTP stuff */
 765     str.Printf("HTTP Request:\r\n");
 766
 767     if (NULL != request) {
 768         Packer pck;
 769         String urlpath_or_slash;
 770
 771         if (request->urlpath.size() != 0)
 772             urlpath_or_slash = request->urlpath;
 773         else
 774             urlpath_or_slash = "/";
 775
 776         str.Printf(SQUIDSBUFPH " " SQUIDSTRINGPH " %s/%d.%d\n",
 777                    SQUIDSBUFPRINT(request->method.image()),
 778                    SQUIDSTRINGPRINT(urlpath_or_slash),
 779                    AnyP::ProtocolType_str[request->http_ver.protocol],
 780                    request->http_ver.major, request->http_ver.minor);
 781         packerToMemInit(&pck, &str);
 782         request->header.packInto(&pck);
 783         packerClean(&pck);
 784     }
 785
 786     str.Printf("\r\n");
 787     /* - FTP stuff */
 788
 789     if (ftp.request) {
 790         str.Printf("FTP Request: %s\r\n", ftp.request);
 791         str.Printf("FTP Reply: %s\r\n", (ftp.reply? ftp.reply:"[none]"));
 792         str.Printf("FTP Msg: ");
 793         wordlistCat(ftp.server_msg, &str);
 794         str.Printf("\r\n");
 795     }
 796
 797     str.Printf("\r\n");
 798     mb->Printf("&body=%s", rfc1738_escape_part(str.buf));
 799     str.clean();
 800     return 0;
 801 }
 802
 803 /// \ingroup ErrorPageInternal
 804 #define CVT_BUF_SZ 512
 805
 806 const char *
 807 ErrorState::Convert(char token, bool building_deny_info_url, bool allowRecursion)
 808 {
 809     static MemBuf mb;
 810     const char *p = NULL;       /* takes priority over mb if set */
 811     int do_quote = 1;
 812     int no_urlescape = 0;       /* if true then item is NOT to be further URL-encoded */
 813     char ntoabuf[MAX_IPSTRLEN];
 814
 815     mb.reset();
 816
 817     switch (token) {
 818
 819     case 'a':
 820 #if USE_AUTH
 821         if (request && request->auth_user_request != NULL)
 822             p = request->auth_user_request->username();
 823         if (!p)
 824 #endif
 825             p = "-";
 826         break;
 827
 828     case 'b':
 829         mb.Printf("%d", getMyPort());
 830         break;
 831
 832     case 'B':
 833         if (building_deny_info_url) break;
 834         p = request ? ftpUrlWith2f(request) : "[no URL]";
 835         break;
 836
 837     case 'c':
 838         if (building_deny_info_url) break;
 839         p = errorPageName(type);
 840         break;
 841
 842     case 'D':
 843         if (!allowRecursion)
 844             p = "%D";  // if recursion is not allowed, do not convert
 845 #if USE_OPENSSL
 846         // currently only SSL error details implemented
 847         else if (detail) {
 848             detail->useRequest(request);
 849             const String &errDetail = detail->toString();
 850             if (errDetail.size() > 0) {
 851                 MemBuf *detail_mb  = ConvertText(errDetail.termedBuf(), false);
 852                 mb.append(detail_mb->content(), detail_mb->contentSize());
 853                 delete detail_mb;
 854                 do_quote = 0;
 855             }
 856         }
 857 #endif
 858         if (!mb.contentSize())
 859             mb.Printf("[No Error Detail]");
 860         break;
 861
 862     case 'e':
 863         mb.Printf("%d", xerrno);
 864         break;
 865
 866     case 'E':
 867         if (xerrno)
 868             mb.Printf("(%d) %s", xerrno, strerror(xerrno));
 869         else
 870             mb.Printf("[No Error]");
 871         break;
 872
 873     case 'f':
 874         if (building_deny_info_url) break;
 875         /* FTP REQUEST LINE */
 876         if (ftp.request)
 877             p = ftp.request;
 878         else
 879             p = "nothing";
 880         break;
 881
 882     case 'F':
 883         if (building_deny_info_url) break;
 884         /* FTP REPLY LINE */
 885         if (ftp.reply)
 886             p = ftp.reply;
 887         else
 888             p = "nothing";
 889         break;
 890
 891     case 'g':
 892         if (building_deny_info_url) break;
 893         /* FTP SERVER RESPONSE */
 894         if (ftp.listing) {
 895             mb.append(ftp.listing->content(), ftp.listing->contentSize());
 896             do_quote = 0;
 897         } else if (ftp.server_msg) {
 898             wordlistCat(ftp.server_msg, &mb);
 899         }
 900         break;
 901
 902     case 'h':
 903         mb.Printf("%s", getMyHostname());
 904         break;
 905
 906     case 'H':
 907         if (request) {
 908             if (request->hier.host[0] != '\0') // if non-empty string.
 909                 p = request->hier.host;
 910             else
 911                 p = request->GetHost();
 912         } else if (!building_deny_info_url)
 913             p = "[unknown host]";
 914         break;
 915
 916     case 'i':
 917         mb.Printf("%s", src_addr.toStr(ntoabuf,MAX_IPSTRLEN));
 918         break;
 919
 920     case 'I':
 921         if (request && request->hier.tcpServer != NULL)
 922             p = request->hier.tcpServer->remote.toStr(ntoabuf,MAX_IPSTRLEN);
 923         else if (!building_deny_info_url)
 924             p = "[unknown]";
 925         break;
 926
 927     case 'l':
 928         if (building_deny_info_url) break;
 929         mb.append(error_stylesheet.content(), error_stylesheet.contentSize());
 930         do_quote = 0;
 931         break;
 932
 933     case 'L':
 934         if (building_deny_info_url) break;
 935         if (Config.errHtmlText) {
 936             mb.Printf("%s", Config.errHtmlText);
 937             do_quote = 0;
 938         } else
 939             p = "[not available]";
 940         break;
 941
 942     case 'm':
 943         if (building_deny_info_url) break;
 944 #if USE_AUTH
 945         p = auth_user_request->denyMessage("[not available]");
 946 #else
 947         p = "-";
 948 #endif
 949         break;
 950
 951     case 'M':
 952         if (request) {
 953             const SBuf &m = request->method.image();
 954             mb.append(m.rawContent(), m.length());
 955         } else if (!building_deny_info_url)
 956             p = "[unknown method]";
 957         break;
 958
 959     case 'o':
 960         p = request ? request->extacl_message.termedBuf() : external_acl_message;
 961         if (!p && !building_deny_info_url)
 962             p = "[not available]";
 963         break;
 964
 965     case 'p':
 966         if (request) {
 967             mb.Printf("%d", (int) request->port);
 968         } else if (!building_deny_info_url) {
 969             p = "[unknown port]";
 970         }
 971         break;
 972
 973     case 'P':
 974         if (request) {
 975             p = request->url.getScheme().c_str();
 976         } else if (!building_deny_info_url) {
 977             p = "[unknown protocol]";
 978         }
 979         break;
 980
 981     case 'R':
 982         if (building_deny_info_url) {
 983             p = (request->urlpath.size() != 0 ? request->urlpath.termedBuf() : "/");
 984             no_urlescape = 1;
 985             break;
 986         }
 987         if (NULL != request) {
 988             Packer pck;
 989             String urlpath_or_slash;
 990
 991             if (request->urlpath.size() != 0)
 992                 urlpath_or_slash = request->urlpath;
 993             else
 994                 urlpath_or_slash = "/";
 995
 996             mb.Printf(SQUIDSBUFPH " " SQUIDSTRINGPH " %s/%d.%d\n",
 997                       SQUIDSBUFPRINT(request->method.image()),
 998                       SQUIDSTRINGPRINT(urlpath_or_slash),
 999                       AnyP::ProtocolType_str[request->http_ver.protocol],
1000                       request->http_ver.major, request->http_ver.minor);
1001             packerToMemInit(&pck, &mb);
1002             request->header.packInto(&pck, true); //hide authorization data
1003             packerClean(&pck);
1004         } else if (request_hdrs) {
1005             p = request_hdrs;
1006         } else {
1007             p = "[no request]";
1008         }
1009         break;
1010
1011     case 's':
1012         /* for backward compat we make %s show the full URL. Drop this in some future release. */
1013         if (building_deny_info_url) {
1014             p = request ? urlCanonical(request) : url;
1015             debugs(0, DBG_CRITICAL, "WARNING: deny_info now accepts coded tags. Use %u to get the full URL instead of %s");
1016         } else
1017             p = visible_appname_string;
1018         break;
1019
1020     case 'S':
1021         if (building_deny_info_url) {
1022             p = visible_appname_string;
1023             break;
1024         }
1025         /* signature may contain %-escapes, recursion */
1026         if (page_id != ERR_SQUID_SIGNATURE) {
1027             const int saved_id = page_id;
1028             page_id = ERR_SQUID_SIGNATURE;
1029             MemBuf *sign_mb = BuildContent();
1030             mb.Printf("%s", sign_mb->content());
1031             sign_mb->clean();
1032             delete sign_mb;
1033             page_id = saved_id;
1034             do_quote = 0;
1035         } else {
1036             /* wow, somebody put %S into ERR_SIGNATURE, stop recursion */
1037             p = "[%S]";
1038         }
1039         break;
1040
1041     case 't':
1042         mb.Printf("%s", Time::FormatHttpd(squid_curtime));
1043         break;
1044
1045     case 'T':
1046         mb.Printf("%s", mkrfc1123(squid_curtime));
1047         break;
1048
1049     case 'U':
1050         /* Using the fake-https version of canonical so error pages see https:// */
1051         /* even when the url-path cannot be shown as more than '*' */
1052         if (request)
1053             p = urlCanonicalFakeHttps(request);
1054         else if (url)
1055             p = url;
1056         else if (!building_deny_info_url)
1057             p = "[no URL]";
1058         break;
1059
1060     case 'u':
1061         if (request)
1062             p = urlCanonical(request);
1063         else if (url)
1064             p = url;
1065         else if (!building_deny_info_url)
1066             p = "[no URL]";
1067         break;
1068
1069     case 'w':
1070         if (Config.adminEmail)
1071             mb.Printf("%s", Config.adminEmail);
1072         else if (!building_deny_info_url)
1073             p = "[unknown]";
1074         break;
1075
1076     case 'W':
1077         if (building_deny_info_url) break;
1078         if (Config.adminEmail && Config.onoff.emailErrData)
1079             Dump(&mb);
1080         no_urlescape = 1;
1081         break;
1082
1083     case 'x':
1084 #if USE_OPENSSL
1085         if (detail)
1086             mb.Printf("%s", detail->errorName());
1087         else
1088 #endif
1089             if (!building_deny_info_url)
1090                 p = "[Unknown Error Code]";
1091         break;
1092
1093     case 'z':
1094         if (building_deny_info_url) break;
1095         if (dnsError.size() > 0)
1096             p = dnsError.termedBuf();
1097         else if (ftp.cwd_msg)
1098             p = ftp.cwd_msg;
1099         else
1100             p = "[unknown]";
1101         break;
1102
1103     case 'Z':
1104         if (building_deny_info_url) break;
1105         if (err_msg)
1106             p = err_msg;
1107         else
1108             p = "[unknown]";
1109         break;
1110
1111     case '%':
1112         p = "%";
1113         break;
1114
1115     default:
1116         mb.Printf("%%%c", token);
1117         do_quote = 0;
1118         break;
1119     }
1120
1121     if (!p)
1122         p = mb.buf;             /* do not use mb after this assignment! */
1123
1124     assert(p);
1125
1126     debugs(4, 3, "errorConvert: %%" << token << " --> '" << p << "'" );
1127
1128     if (do_quote)
1129         p = html_quote(p);
1130
1131     if (building_deny_info_url && !no_urlescape)
1132         p = rfc1738_escape_part(p);
1133
1134     return p;
1135 }
1136
1137 void
1138 ErrorState::DenyInfoLocation(const char *name, HttpRequest *aRequest, MemBuf &result)
1139 {
1140     char const *m = name;
1141     char const *p = m;
1142     char const *t;
1143
1144     if (m[0] == '3')
1145         m += 4; // skip "3xx:"
1146
1147     while ((p = strchr(m, '%'))) {
1148         result.append(m, p - m);       /* copy */
1149         t = Convert(*++p, true, true);       /* convert */
1150         result.Printf("%s", t);        /* copy */
1151         m = p + 1;                     /* advance */
1152     }
1153
1154     if (*m)
1155         result.Printf("%s", m);        /* copy tail */
1156
1157     assert((size_t)result.contentSize() == strlen(result.content()));
1158 }
1159
1160 HttpReply *
1161 ErrorState::BuildHttpReply()
1162 {
1163     HttpReply *rep = new HttpReply;
1164     const char *name = errorPageName(page_id);
1165     /* no LMT for error pages; error pages expire immediately */
1166
1167     if (name[0] == '3' || (name[0] != '2' && name[0] != '4' && name[0] != '5' && strchr(name, ':'))) {
1168         /* Redirection */
1169         Http::StatusCode status = Http::scFound;
1170         // Use configured 3xx reply status if set.
1171         if (name[0] == '3')
1172             status = httpStatus;
1173         else {
1174             // Use 307 for HTTP/1.1 non-GET/HEAD requests.
1175             if (request->method != Http::METHOD_GET && request->method != Http::METHOD_HEAD && request->http_ver >= Http::ProtocolVersion(1,1))
1176                 status = Http::scTemporaryRedirect;
1177         }
1178
1179         rep->setHeaders(status, NULL, "text/html;charset=utf-8", 0, 0, -1);
1180
1181         if (request) {
1182             MemBuf redirect_location;
1183             redirect_location.init();
1184             DenyInfoLocation(name, request, redirect_location);
1185             httpHeaderPutStrf(&rep->header, HDR_LOCATION, "%s", redirect_location.content() );
1186         }
1187
1188         httpHeaderPutStrf(&rep->header, HDR_X_SQUID_ERROR, "%d %s", httpStatus, "Access Denied");
1189     } else {
1190         MemBuf *content = BuildContent();
1191         rep->setHeaders(httpStatus, NULL, "text/html;charset=utf-8", content->contentSize(), 0, -1);
1192         /*
1193          * include some information for downstream caches. Implicit
1194          * replaceable content. This isn't quite sufficient. xerrno is not
1195          * necessarily meaningful to another system, so we really should
1196          * expand it. Additionally, we should identify ourselves. Someone
1197          * might want to know. Someone _will_ want to know OTOH, the first
1198          * X-CACHE-MISS entry should tell us who.
1199          */
1200         httpHeaderPutStrf(&rep->header, HDR_X_SQUID_ERROR, "%s %d", name, xerrno);
1201
1202 #if USE_ERR_LOCALES
1203         /*
1204          * If error page auto-negotiate is enabled in any way, send the Vary.
1205          * RFC 2616 section 13.6 and 14.44 says MAY and SHOULD do this.
1206          * We have even better reasons though:
1207          * see http://wiki.squid-cache.org/KnowledgeBase/VaryNotCaching
1208          */
1209         if (!Config.errorDirectory) {
1210             /* We 'negotiated' this ONLY from the Accept-Language. */
1211             rep->header.delById(HDR_VARY);
1212             rep->header.putStr(HDR_VARY, "Accept-Language");
1213         }
1214
1215         /* add the Content-Language header according to RFC section 14.12 */
1216         if (err_language) {
1217             rep->header.putStr(HDR_CONTENT_LANGUAGE, err_language);
1218         } else
1219 #endif /* USE_ERROR_LOCALES */
1220         {
1221             /* default templates are in English */
1222             /* language is known unless error_directory override used */
1223             if (!Config.errorDirectory)
1224                 rep->header.putStr(HDR_CONTENT_LANGUAGE, "en");
1225         }
1226
1227         rep->body.setMb(content);
1228         /* do not memBufClean() or delete the content, it was absorbed by httpBody */
1229     }
1230
1231     // Make sure error codes get back to the client side for logging and
1232     // error tracking.
1233     if (request) {
1234         int edc = ERR_DETAIL_NONE; // error detail code
1235 #if USE_OPENSSL
1236         if (detail)
1237             edc = detail->errorNo();
1238         else
1239 #endif
1240             if (detailCode)
1241                 edc = detailCode;
1242             else
1243                 edc = xerrno;
1244         request->detailError(type, edc);
1245     }
1246
1247     return rep;
1248 }
1249
1250 MemBuf *
1251 ErrorState::BuildContent()
1252 {
1253     const char *m = NULL;
1254
1255     assert(page_id > ERR_NONE && page_id < error_page_count);
1256
1257 #if USE_ERR_LOCALES
1258     ErrorPageFile *localeTmpl = NULL;
1259
1260     /** error_directory option in squid.conf overrides translations.
1261      * Custom errors are always found either in error_directory or the templates directory.
1262      * Otherwise locate the Accept-Language header
1263      */
1264     if (!Config.errorDirectory && page_id < ERR_MAX) {
1265         if (err_language && err_language != Config.errorDefaultLanguage)
1266             safe_free(err_language);
1267
1268         localeTmpl = new ErrorPageFile(err_type_str[page_id], static_cast<err_type>(page_id));
1269         if (localeTmpl->loadFor(request)) {
1270             m = localeTmpl->text();
1271             assert(localeTmpl->language());
1272             err_language = xstrdup(localeTmpl->language());
1273         }
1274     }
1275 #endif /* USE_ERR_LOCALES */
1276
1277     /** \par
1278      * If client-specific error templates are not enabled or available.
1279      * fall back to the old style squid.conf settings.
1280      */
1281     if (!m) {
1282         m = error_text[page_id];
1283 #if USE_ERR_LOCALES
1284         if (!Config.errorDirectory)
1285             err_language = Config.errorDefaultLanguage;
1286 #endif
1287         debugs(4, 2, HERE << "No existing error page language negotiated for " << errorPageName(page_id) << ". Using default error file.");
1288     }
1289
1290     MemBuf *result = ConvertText(m, true);
1291 #if USE_ERR_LOCALES
1292     if (localeTmpl)
1293         delete localeTmpl;
1294 #endif
1295     return result;
1296 }
1297
1298 MemBuf *ErrorState::ConvertText(const char *text, bool allowRecursion)
1299 {
1300     MemBuf *content = new MemBuf;
1301     const char *p;
1302     const char *m = text;
1303     assert(m);
1304     content->init();
1305
1306     while ((p = strchr(m, '%'))) {
1307         content->append(m, p - m);      /* copy */
1308         const char *t = Convert(*++p, false, allowRecursion);   /* convert */
1309         content->Printf("%s", t);       /* copy */
1310         m = p + 1;                      /* advance */
1311     }
1312
1313     if (*m)
1314         content->Printf("%s", m);       /* copy tail */
1315
1316     content->terminate();
1317
1318     assert((size_t)content->contentSize() == strlen(content->content()));
1319
1320     return content;
1321 }