src/errorpage.cc

   1 /*
   2  * Copyright (C) 1996-2022 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 04    Error Generation */
  10
  11 #include "squid.h"
  12 #include "AccessLogEntry.h"
  13 #include "cache_cf.h"
  14 #include "clients/forward.h"
  15 #include "comm/Connection.h"
  16 #include "comm/Write.h"
  17 #include "error/Detail.h"
  18 #include "error/SysErrorDetail.h"
  19 #include "errorpage.h"
  20 #include "fde.h"
  21 #include "format/Format.h"
  22 #include "fs_io.h"
  23 #include "html_quote.h"
  24 #include "HttpHeaderTools.h"
  25 #include "HttpReply.h"
  26 #include "HttpRequest.h"
  27 #include "MemBuf.h"
  28 #include "MemObject.h"
  29 #include "rfc1738.h"
  30 #include "sbuf/Stream.h"
  31 #include "SquidConfig.h"
  32 #include "Store.h"
  33 #include "tools.h"
  34 #include "wordlist.h"
  35 #if USE_AUTH
  36 #include "auth/UserRequest.h"
  37 #endif
  38 #if USE_OPENSSL
  39 #include "ssl/ErrorDetailManager.h"
  40 #endif
  41
  42 /**
  43  \defgroup ErrorPageInternal Error Page Internals
  44  \ingroup ErrorPageAPI
  45  *
  46  \section ErrorPagesAbstract Abstract:
  47  *   These routines are used to generate error messages to be
  48  *   sent to clients.  The error type is used to select between
  49  *   the various message formats. (formats are stored in the
  50  *   Config.errorDirectory)
  51  */
  52
  53 #if !defined(DEFAULT_SQUID_ERROR_DIR)
  54 /** Where to look for errors if config path fails.
  55  \note Please use ./configure --datadir=/path instead of patching
  56  */
  57 #define DEFAULT_SQUID_ERROR_DIR   DEFAULT_SQUID_DATA_DIR"/errors"
  58 #endif
  59
  60 /// \ingroup ErrorPageInternal
  61 CBDATA_CLASS_INIT(ErrorState);
  62
  63 const SBuf ErrorState::LogformatMagic("@Squid{");
  64
  65 /* local types */
  66
  67 /// an error page created from admin-configurable metadata (e.g. deny_info)
  68 class ErrorDynamicPageInfo {
  69 public:
  70     ErrorDynamicPageInfo(const int anId, const char *aName, const SBuf &aCfgLocation);
  71     ~ErrorDynamicPageInfo() { xfree(page_name); }
  72
  73     /// error_text[] index for response body (unused in redirection responses)
  74     int id;
  75
  76     /// Primary deny_info parameter:
  77     /// * May start with an HTTP status code.
  78     /// * Either a well-known error page name, a filename, or a redirect URL.
  79     char *page_name;
  80
  81     /// admin-configured HTTP Location header value for redirection responses
  82     const char *uri;
  83
  84     /// admin-configured name for the error page template (custom or standard)
  85     const char *filename;
  86
  87     /// deny_info directive position in squid.conf (for reporting)
  88     SBuf cfgLocation;
  89
  90     // XXX: Misnamed. Not just for redirects.
  91     /// admin-configured HTTP status code
  92     Http::StatusCode page_redirect;
  93
  94 private:
  95     // no copying of any kind
  96     ErrorDynamicPageInfo(ErrorDynamicPageInfo &&) = delete;
  97 };
  98
  99 namespace ErrorPage {
 100
 101 /// state and parameters shared by several ErrorState::compile*() methods
 102 class Build
 103 {
 104 public:
 105     SBuf output; ///< compilation result
 106     const char *input = nullptr; ///< template bytes that need to be compiled
 107     bool building_deny_info_url = false; ///< whether we compile deny_info URI
 108     bool allowRecursion = false; ///< whether top-level compile() calls are OK
 109 };
 110
 111 /// pretty-prints error page/deny_info building error
 112 class BuildErrorPrinter
 113 {
 114 public:
 115     BuildErrorPrinter(const SBuf &anInputLocation, int aPage, const char *aMsg, const char *aNear): inputLocation(anInputLocation), page_id(aPage), msg(aMsg), near(aNear) {}
 116
 117     /// reports error details (for admin-visible exceptions and debugging)
 118     std::ostream &print(std::ostream &) const;
 119
 120     /// print() helper to report where the error was found
 121     std::ostream &printLocation(std::ostream &os) const;
 122
 123     /* saved constructor parameters */
 124     const SBuf &inputLocation;
 125     const int page_id;
 126     const char *msg;
 127     const char *near;
 128 };
 129
 130 static inline std::ostream &
 131 operator <<(std::ostream &os, const BuildErrorPrinter &context)
 132 {
 133     return context.print(os);
 134 }
 135
 136 static const char *IsDenyInfoUri(const int page_id);
 137
 138 static void ImportStaticErrorText(const int page_id, const char *text, const SBuf &inputLocation);
 139 static void ValidateStaticError(const int page_id, const SBuf &inputLocation);
 140
 141 } // namespace ErrorPage
 142
 143 /* local constant and vars */
 144
 145 /**
 146  \ingroup ErrorPageInternal
 147  *
 148  \note  hard coded error messages are not appended with %S
 149  *      automagically to give you more control on the format
 150  */
 151 static const struct {
 152     int type;           /* and page_id */
 153     const char *text;
 154 }
 155
 156 error_hard_text[] = {
 157
 158     {
 159         ERR_SQUID_SIGNATURE,
 160         "\n<br>\n"
 161         "<hr>\n"
 162         "<div id=\"footer\">\n"
 163         "Generated %T by %h (%s)\n"
 164         "</div>\n"
 165         "</body></html>\n"
 166     },
 167     {
 168         TCP_RESET,
 169         "reset"
 170     },
 171     {
 172         ERR_CLIENT_GONE,
 173         "unexpected client disconnect"
 174     },
 175     {
 176         ERR_SECURE_ACCEPT_FAIL,
 177         "secure accept fail"
 178     },
 179     {
 180         ERR_REQUEST_START_TIMEOUT,
 181         "request start timedout"
 182     },
 183     {
 184         MGR_INDEX,
 185         "mgr_index"
 186     }
 187 };
 188
 189 /// \ingroup ErrorPageInternal
 190 static std::vector<ErrorDynamicPageInfo *> ErrorDynamicPages;
 191
 192 /* local prototypes */
 193
 194 /// \ingroup ErrorPageInternal
 195 static const int error_hard_text_count = sizeof(error_hard_text) / sizeof(*error_hard_text);
 196
 197 /// \ingroup ErrorPageInternal
 198 static char **error_text = nullptr;
 199
 200 /// \ingroup ErrorPageInternal
 201 static int error_page_count = 0;
 202
 203 /// \ingroup ErrorPageInternal
 204 static MemBuf error_stylesheet;
 205
 206 static const char *errorFindHardText(err_type type);
 207 static IOCB errorSendComplete;
 208
 209 /// \ingroup ErrorPageInternal
 210 /// manages an error page template
 211 class ErrorPageFile: public TemplateFile
 212 {
 213 public:
 214     ErrorPageFile(const char *name, const err_type code) : TemplateFile(name, code) {}
 215
 216     /// The template text data read from disk
 217     const char *text() { return template_.c_str(); }
 218
 219 protected:
 220     virtual void setDefault() override {
 221         template_ = "Internal Error: Missing Template ";
 222         template_.append(templateName.termedBuf());
 223     }
 224 };
 225
 226 /// \ingroup ErrorPageInternal
 227 static err_type &
 228 operator++ (err_type &anErr)
 229 {
 230     int tmp = (int)anErr;
 231     anErr = (err_type)(++tmp);
 232     return anErr;
 233 }
 234
 235 /// \ingroup ErrorPageInternal
 236 static int
 237 operator -(err_type const &anErr, err_type const &anErr2)
 238 {
 239     return (int)anErr - (int)anErr2;
 240 }
 241
 242 /// \return deny_info URL if the given page is a deny_info page with a URL
 243 /// \return nullptr otherwise
 244 static const char *
 245 ErrorPage::IsDenyInfoUri(const int page_id)
 246 {
 247     if (ERR_MAX <= page_id && page_id < error_page_count)
 248         return ErrorDynamicPages.at(page_id - ERR_MAX)->uri; // may be nil
 249     return nullptr;
 250 }
 251
 252 void
 253 errorInitialize(void)
 254 {
 255     using ErrorPage::ImportStaticErrorText;
 256
 257     err_type i;
 258     const char *text;
 259     error_page_count = ERR_MAX + ErrorDynamicPages.size();
 260     error_text = static_cast<char **>(xcalloc(error_page_count, sizeof(char *)));
 261
 262     for (i = ERR_NONE, ++i; i < error_page_count; ++i) {
 263         safe_free(error_text[i]);
 264
 265         if ((text = errorFindHardText(i))) {
 266             /**\par
 267              * Index any hard-coded error text into defaults.
 268              */
 269             static const SBuf builtIn("built-in");
 270             ImportStaticErrorText(i, text, builtIn);
 271
 272         } else if (i < ERR_MAX) {
 273             /**\par
 274              * Index precompiled fixed template files from one of two sources:
 275              *  (a) default language translation directory (error_default_language)
 276              *  (b) admin specified custom directory (error_directory)
 277              */
 278             ErrorPageFile errTmpl(err_type_str[i], i);
 279             errTmpl.loadDefault();
 280             ImportStaticErrorText(i, errTmpl.text(), errTmpl.filename);
 281         } else {
 282             /** \par
 283              * Index any unknown file names used by deny_info.
 284              */
 285             ErrorDynamicPageInfo *info = ErrorDynamicPages.at(i - ERR_MAX);
 286             assert(info && info->id == i && info->page_name);
 287
 288             if (info->filename) {
 289                 /** But only if they are not redirection URL. */
 290                 ErrorPageFile errTmpl(info->filename, ERR_MAX);
 291                 errTmpl.loadDefault();
 292                 ImportStaticErrorText(i, errTmpl.text(), errTmpl.filename);
 293             } else {
 294                 assert(info->uri);
 295                 ErrorPage::ValidateStaticError(i, info->cfgLocation);
 296             }
 297         }
 298     }
 299
 300     error_stylesheet.reset();
 301
 302     // look for and load stylesheet into global MemBuf for it.
 303     if (Config.errorStylesheet) {
 304         ErrorPageFile tmpl("StylesSheet", ERR_MAX);
 305         tmpl.loadFromFile(Config.errorStylesheet);
 306         error_stylesheet.appendf("%s",tmpl.text());
 307     }
 308
 309 #if USE_OPENSSL
 310     Ssl::errorDetailInitialize();
 311 #endif
 312 }
 313
 314 void
 315 errorClean(void)
 316 {
 317     if (error_text) {
 318         int i;
 319
 320         for (i = ERR_NONE + 1; i < error_page_count; ++i)
 321             safe_free(error_text[i]);
 322
 323         safe_free(error_text);
 324     }
 325
 326     while (!ErrorDynamicPages.empty()) {
 327         delete ErrorDynamicPages.back();
 328         ErrorDynamicPages.pop_back();
 329     }
 330
 331     error_page_count = 0;
 332
 333 #if USE_OPENSSL
 334     Ssl::errorDetailClean();
 335 #endif
 336 }
 337
 338 /// \ingroup ErrorPageInternal
 339 static const char *
 340 errorFindHardText(err_type type)
 341 {
 342     int i;
 343
 344     for (i = 0; i < error_hard_text_count; ++i)
 345         if (error_hard_text[i].type == type)
 346             return error_hard_text[i].text;
 347
 348     return nullptr;
 349 }
 350
 351 TemplateFile::TemplateFile(const char *name, const err_type code): silent(false), wasLoaded(false), templateName(name), templateCode(code)
 352 {
 353     assert(name);
 354 }
 355
 356 void
 357 TemplateFile::loadDefault()
 358 {
 359     if (loaded()) // already loaded?
 360         return;
 361
 362     /** test error_directory configured location */
 363     if (Config.errorDirectory) {
 364         char path[MAXPATHLEN];
 365         snprintf(path, sizeof(path), "%s/%s", Config.errorDirectory, templateName.termedBuf());
 366         loadFromFile(path);
 367     }
 368
 369 #if USE_ERR_LOCALES
 370     /** test error_default_language location */
 371     if (!loaded() && Config.errorDefaultLanguage) {
 372         if (!tryLoadTemplate(Config.errorDefaultLanguage)) {
 373             debugs(1, (templateCode < TCP_RESET ? DBG_CRITICAL : 3), "ERROR: Unable to load default error language files. Reset to backups.");
 374         }
 375     }
 376 #endif
 377
 378     /* test default location if failed (templates == English translation base templates) */
 379     if (!loaded()) {
 380         tryLoadTemplate("templates");
 381     }
 382
 383     /* giving up if failed */
 384     if (!loaded()) {
 385         debugs(1, (templateCode < TCP_RESET ? DBG_CRITICAL : 3), "WARNING: failed to find or read error text file " << templateName);
 386         template_.clear();
 387         setDefault();
 388         wasLoaded = true;
 389     }
 390 }
 391
 392 bool
 393 TemplateFile::tryLoadTemplate(const char *lang)
 394 {
 395     assert(lang);
 396
 397     char path[MAXPATHLEN];
 398     /* TODO: prep the directory path string to prevent snprintf ... */
 399     snprintf(path, sizeof(path), "%s/%s/%s",
 400              DEFAULT_SQUID_ERROR_DIR, lang, templateName.termedBuf());
 401     path[MAXPATHLEN-1] = '\0';
 402
 403     if (loadFromFile(path))
 404         return true;
 405
 406 #if HAVE_GLOB
 407     if ( strlen(lang) == 2) {
 408         /* TODO glob the error directory for sub-dirs matching: <tag> '-*'   */
 409         /* use first result. */
 410         debugs(4,2, "wildcard fallback errors not coded yet.");
 411     }
 412 #endif
 413
 414     return false;
 415 }
 416
 417 bool
 418 TemplateFile::loadFromFile(const char *path)
 419 {
 420     int fd;
 421     char buf[4096];
 422     ssize_t len;
 423
 424     if (loaded()) // already loaded?
 425         return true;
 426
 427     fd = file_open(path, O_RDONLY | O_TEXT);
 428
 429     if (fd < 0) {
 430         /* with dynamic locale negotiation we may see some failures before a success. */
 431         if (!silent && templateCode < TCP_RESET) {
 432             int xerrno = errno;
 433             debugs(4, DBG_CRITICAL, "ERROR: loading file '" << path << "': " << xstrerr(xerrno));
 434         }
 435         wasLoaded = false;
 436         return wasLoaded;
 437     }
 438
 439     template_.clear();
 440     while ((len = FD_READ_METHOD(fd, buf, sizeof(buf))) > 0) {
 441         template_.append(buf, len);
 442     }
 443
 444     if (len < 0) {
 445         int xerrno = errno;
 446         file_close(fd);
 447         debugs(4, DBG_CRITICAL, MYNAME << "ERROR: failed to fully read: '" << path << "': " << xstrerr(xerrno));
 448         wasLoaded = false;
 449         return false;
 450     }
 451
 452     file_close(fd);
 453
 454     filename = SBuf(path);
 455
 456     if (!parse()) {
 457         debugs(4, DBG_CRITICAL, "ERROR: parsing error in template file: " << path);
 458         wasLoaded = false;
 459         return false;
 460     }
 461
 462     wasLoaded = true;
 463     return wasLoaded;
 464 }
 465
 466 bool strHdrAcptLangGetItem(const String &hdr, char *lang, int langLen, size_t &pos)
 467 {
 468     while (pos < hdr.size()) {
 469
 470         /* skip any initial whitespace. */
 471         while (pos < hdr.size() && xisspace(hdr[pos]))
 472             ++pos;
 473
 474         /*
 475          * Header value format:
 476          *  - sequence of whitespace delimited tags
 477          *  - each tag may suffix with ';'.* which we can ignore.
 478          *  - IFF a tag contains only two characters we can wildcard ANY translations matching: <it> '-'? .*
 479          *    with preference given to an exact match.
 480          */
 481         bool invalid_byte = false;
 482         char *dt = lang;
 483         while (pos < hdr.size() && hdr[pos] != ';' && hdr[pos] != ',' && !xisspace(hdr[pos]) && dt < (lang + (langLen -1)) ) {
 484             if (!invalid_byte) {
 485 #if USE_HTTP_VIOLATIONS
 486                 // if accepting violations we may as well accept some broken browsers
 487                 //  which may send us the right code, wrong ISO formatting.
 488                 if (hdr[pos] == '_')
 489                     *dt = '-';
 490                 else
 491 #endif
 492                     *dt = xtolower(hdr[pos]);
 493                 // valid codes only contain A-Z, hyphen (-) and *
 494                 if (*dt != '-' && *dt != '*' && (*dt < 'a' || *dt > 'z') )
 495                     invalid_byte = true;
 496                 else
 497                     ++dt; // move to next destination byte.
 498             }
 499             ++pos;
 500         }
 501         *dt = '\0'; // nul-terminated the filename content string before system use.
 502
 503         // if we terminated the tag on garbage or ';' we need to skip to the next ',' or end of header.
 504         while (pos < hdr.size() && hdr[pos] != ',')
 505             ++pos;
 506
 507         if (pos < hdr.size() && hdr[pos] == ',')
 508             ++pos;
 509
 510         debugs(4, 9, "STATE: lang=" << lang << ", pos=" << pos << ", buf='" << ((pos < hdr.size()) ? hdr.substr(pos,hdr.size()) : "") << "'");
 511
 512         /* if we found anything we might use, try it. */
 513         if (*lang != '\0' && !invalid_byte)
 514             return true;
 515     }
 516     return false;
 517 }
 518
 519 bool
 520 TemplateFile::loadFor(const HttpRequest *request)
 521 {
 522     String hdr;
 523
 524 #if USE_ERR_LOCALES
 525     if (loaded()) // already loaded?
 526         return true;
 527
 528     if (!request || !request->header.getList(Http::HdrType::ACCEPT_LANGUAGE, &hdr))
 529         return false;
 530
 531     char lang[256];
 532     size_t pos = 0; // current parsing position in header string
 533
 534     debugs(4, 6, "Testing Header: '" << hdr << "'");
 535
 536     while ( strHdrAcptLangGetItem(hdr, lang, 256, pos) ) {
 537
 538         /* wildcard uses the configured default language */
 539         if (lang[0] == '*' && lang[1] == '\0') {
 540             debugs(4, 6, "Found language '" << lang << "'. Using configured default.");
 541             return false;
 542         }
 543
 544         debugs(4, 6, "Found language '" << lang << "', testing for available template");
 545
 546         if (tryLoadTemplate(lang)) {
 547             /* store the language we found for the Content-Language reply header */
 548             errLanguage = lang;
 549             break;
 550         } else if (Config.errorLogMissingLanguages) {
 551             debugs(4, DBG_IMPORTANT, "WARNING: Error Pages Missing Language: " << lang);
 552         }
 553     }
 554 #else
 555     (void)request;
 556 #endif
 557
 558     return loaded();
 559 }
 560
 561 ErrorDynamicPageInfo::ErrorDynamicPageInfo(const int anId, const char *aName, const SBuf &aCfgLocation):
 562     id(anId),
 563     page_name(xstrdup(aName)),
 564     uri(nullptr),
 565     filename(nullptr),
 566     cfgLocation(aCfgLocation),
 567     page_redirect(static_cast<Http::StatusCode>(atoi(page_name)))
 568 {
 569     const char *filenameOrUri = nullptr;
 570     if (xisdigit(*page_name)) {
 571         if (const char *statusCodeEnd = strchr(page_name, ':'))
 572             filenameOrUri = statusCodeEnd + 1;
 573     } else {
 574         assert(!page_redirect);
 575         filenameOrUri = page_name;
 576     }
 577
 578     // Guessed uri, filename, or both values may be nil or malformed.
 579     // They are validated later.
 580     if (!page_redirect) {
 581         if (filenameOrUri && strchr(filenameOrUri, ':')) // looks like a URL
 582             uri = filenameOrUri;
 583         else
 584             filename = filenameOrUri;
 585     }
 586     else if (page_redirect/100 == 3) {
 587         // redirects imply a URL
 588         uri = filenameOrUri;
 589     } else {
 590         // non-redirects imply an error page name
 591         filename = filenameOrUri;
 592     }
 593
 594     const auto info = this; // source code change reduction hack
 595     // TODO: Move and refactor to avoid self_destruct()s in reconfigure.
 596
 597     /* WARNING on redirection status:
 598      * 2xx are permitted, but not documented officially.
 599      * - might be useful for serving static files (PAC etc) in special cases
 600      * 3xx require a URL suitable for Location: header.
 601      * - the current design does not allow for a Location: URI as well as a local file template
 602      *   although this possibility is explicitly permitted in the specs.
 603      * 4xx-5xx require a local file template.
 604      * - sending Location: on these codes with no body is invalid by the specs.
 605      * - current result is Squid crashing or XSS problems as dynamic deny_info load random disk files.
 606      * - a future redesign of the file loading may result in loading remote objects sent inline as local body.
 607      */
 608     if (info->page_redirect == Http::scNone)
 609         ; // special case okay.
 610     else if (info->page_redirect < 200 || info->page_redirect > 599) {
 611         // out of range
 612         debugs(0, DBG_CRITICAL, "FATAL: status " << info->page_redirect << " is not valid on '" << page_name << "'");
 613         self_destruct();
 614     } else if ( /* >= 200 && */ info->page_redirect < 300 && strchr(&(page_name[4]), ':')) {
 615         // 2xx require a local template file
 616         debugs(0, DBG_CRITICAL, "FATAL: status " << info->page_redirect << " requires a template on '" << page_name << "'");
 617         self_destruct();
 618     } else if (info->page_redirect >= 300 && info->page_redirect <= 399 && !strchr(&(page_name[4]), ':')) {
 619         // 3xx require an absolute URL
 620         debugs(0, DBG_CRITICAL, "FATAL: status " << info->page_redirect << " requires a URL on '" << page_name << "'");
 621         self_destruct();
 622     } else if (info->page_redirect >= 400 /* && <= 599 */ && strchr(&(page_name[4]), ':')) {
 623         // 4xx/5xx require a local template file
 624         debugs(0, DBG_CRITICAL, "FATAL: status " << info->page_redirect << " requires a template on '" << page_name << "'");
 625         self_destruct();
 626     }
 627     // else okay.
 628 }
 629
 630 /// \ingroup ErrorPageInternal
 631 static int
 632 errorPageId(const char *page_name)
 633 {
 634     for (int i = 0; i < ERR_MAX; ++i) {
 635         if (strcmp(err_type_str[i], page_name) == 0)
 636             return i;
 637     }
 638
 639     for (size_t j = 0; j < ErrorDynamicPages.size(); ++j) {
 640         if (strcmp(ErrorDynamicPages[j]->page_name, page_name) == 0)
 641             return j + ERR_MAX;
 642     }
 643
 644     return ERR_NONE;
 645 }
 646
 647 err_type
 648 errorReservePageId(const char *page_name, const SBuf &cfgLocation)
 649 {
 650     int id = errorPageId(page_name);
 651
 652     if (id == ERR_NONE) {
 653         id = ERR_MAX + ErrorDynamicPages.size();
 654         const auto info = new ErrorDynamicPageInfo(id, page_name, cfgLocation);
 655         ErrorDynamicPages.push_back(info);
 656     }
 657
 658     return (err_type)id;
 659 }
 660
 661 /// \ingroup ErrorPageInternal
 662 const char *
 663 errorPageName(int pageId)
 664 {
 665     if (pageId >= ERR_NONE && pageId < ERR_MAX)     /* common case */
 666         return err_type_str[pageId];
 667
 668     if (pageId >= ERR_MAX && pageId - ERR_MAX < (ssize_t)ErrorDynamicPages.size())
 669         return ErrorDynamicPages[pageId - ERR_MAX]->page_name;
 670
 671     return "ERR_UNKNOWN";   /* should not happen */
 672 }
 673
 674 ErrorState *
 675 ErrorState::NewForwarding(err_type type, HttpRequestPointer &request, const AccessLogEntry::Pointer &ale)
 676 {
 677     const Http::StatusCode status = (request && request->flags.needValidation) ?
 678                                     Http::scGatewayTimeout : Http::scServiceUnavailable;
 679     return new ErrorState(type, status, request.getRaw(), ale);
 680 }
 681
 682 ErrorState::ErrorState(err_type t) :
 683     type(t),
 684     page_id(t),
 685     callback(nullptr)
 686 {
 687 }
 688
 689 ErrorState::ErrorState(err_type t, Http::StatusCode status, HttpRequest * req, const AccessLogEntry::Pointer &anAle) :
 690     ErrorState(t)
 691 {
 692     if (page_id >= ERR_MAX && ErrorDynamicPages[page_id - ERR_MAX]->page_redirect != Http::scNone)
 693         httpStatus = ErrorDynamicPages[page_id - ERR_MAX]->page_redirect;
 694     else
 695         httpStatus = status;
 696
 697     if (req) {
 698         request = req;
 699         src_addr = req->client_addr;
 700     }
 701
 702     ale = anAle;
 703 }
 704
 705 ErrorState::ErrorState(HttpRequest * req, HttpReply *errorReply) :
 706     ErrorState(ERR_RELAY_REMOTE)
 707 {
 708     Must(errorReply);
 709     response_ = errorReply;
 710     httpStatus = errorReply->sline.status();
 711
 712     if (req) {
 713         request = req;
 714         src_addr = req->client_addr;
 715     }
 716 }
 717
 718 void
 719 errorAppendEntry(StoreEntry * entry, ErrorState * err)
 720 {
 721     assert(entry->mem_obj != nullptr);
 722     assert (entry->isEmpty());
 723     debugs(4, 4, "storing " << err << " in " << *entry);
 724
 725     if (entry->store_status != STORE_PENDING) {
 726         debugs(4, 2, "Skipping error page due to store_status: " << entry->store_status);
 727         /*
 728          * If the entry is not STORE_PENDING, then no clients
 729          * care about it, and we don't need to generate an
 730          * error message
 731          */
 732         assert(EBIT_TEST(entry->flags, ENTRY_ABORTED));
 733         assert(entry->mem_obj->nclients == 0);
 734         delete err;
 735         return;
 736     }
 737
 738     if (err->page_id == TCP_RESET) {
 739         if (err->request) {
 740             debugs(4, 2, "RSTing this reply");
 741             err->request->flags.resetTcp = true;
 742         }
 743     }
 744
 745     entry->storeErrorResponse(err->BuildHttpReply());
 746     delete err;
 747 }
 748
 749 void
 750 errorSend(const Comm::ConnectionPointer &conn, ErrorState * err)
 751 {
 752     debugs(4, 3, conn << ", err=" << err);
 753     assert(Comm::IsConnOpen(conn));
 754
 755     HttpReplyPointer rep(err->BuildHttpReply());
 756
 757     MemBuf *mb = rep->pack();
 758     AsyncCall::Pointer call = commCbCall(78, 5, "errorSendComplete",
 759                                          CommIoCbPtrFun(&errorSendComplete, err));
 760     Comm::Write(conn, mb, call);
 761     delete mb;
 762 }
 763
 764 /**
 765  \ingroup ErrorPageAPI
 766  *
 767  * Called by commHandleWrite() after data has been written
 768  * to the client socket.
 769  *
 770  \note If there is a callback, the callback is responsible for
 771  *     closing the FD, otherwise we do it ourselves.
 772  */
 773 static void
 774 errorSendComplete(const Comm::ConnectionPointer &conn, char *, size_t size, Comm::Flag errflag, int, void *data)
 775 {
 776     ErrorState *err = static_cast<ErrorState *>(data);
 777     debugs(4, 3, conn << ", size=" << size);
 778
 779     if (errflag != Comm::ERR_CLOSING) {
 780         if (err->callback) {
 781             debugs(4, 3, "errorSendComplete: callback");
 782             err->callback(conn->fd, err->callback_data, size);
 783         } else {
 784             debugs(4, 3, "errorSendComplete: comm_close");
 785             conn->close();
 786         }
 787     }
 788
 789     delete err;
 790 }
 791
 792 ErrorState::~ErrorState()
 793 {
 794     safe_free(redirect_url);
 795     safe_free(url);
 796     safe_free(request_hdrs);
 797     wordlistDestroy(&ftp.server_msg);
 798     safe_free(ftp.request);
 799     safe_free(ftp.reply);
 800     safe_free(err_msg);
 801 #if USE_ERR_LOCALES
 802     if (err_language != Config.errorDefaultLanguage)
 803 #endif
 804         safe_free(err_language);
 805 }
 806
 807 int
 808 ErrorState::Dump(MemBuf * mb)
 809 {
 810     MemBuf str;
 811     char ntoabuf[MAX_IPSTRLEN];
 812
 813     str.reset();
 814     /* email subject line */
 815     str.appendf("CacheErrorInfo - %s", errorPageName(type));
 816     mb->appendf("?subject=%s", rfc1738_escape_part(str.buf));
 817     str.reset();
 818     /* email body */
 819     str.appendf("CacheHost: %s\r\n", getMyHostname());
 820     /* - Err Msgs */
 821     str.appendf("ErrPage: %s\r\n", errorPageName(type));
 822
 823     if (xerrno) {
 824         str.appendf("Err: (%d) %s\r\n", xerrno, strerror(xerrno));
 825     } else {
 826         str.append("Err: [none]\r\n", 13);
 827     }
 828 #if USE_AUTH
 829     if (auth_user_request.getRaw() && auth_user_request->denyMessage())
 830         str.appendf("Auth ErrMsg: %s\r\n", auth_user_request->denyMessage());
 831 #endif
 832     if (dnsError.size() > 0)
 833         str.appendf("DNS ErrMsg: %s\r\n", dnsError.termedBuf());
 834
 835     /* - TimeStamp */
 836     str.appendf("TimeStamp: %s\r\n\r\n", Time::FormatRfc1123(squid_curtime));
 837
 838     /* - IP stuff */
 839     str.appendf("ClientIP: %s\r\n", src_addr.toStr(ntoabuf,MAX_IPSTRLEN));
 840
 841     if (request && request->hier.host[0] != '\0') {
 842         str.appendf("ServerIP: %s\r\n", request->hier.host);
 843     }
 844
 845     str.append("\r\n", 2);
 846     /* - HTTP stuff */
 847     str.append("HTTP Request:\r\n", 15);
 848     if (request) {
 849         str.appendf(SQUIDSBUFPH " " SQUIDSBUFPH " %s/%d.%d\n",
 850                     SQUIDSBUFPRINT(request->method.image()),
 851                     SQUIDSBUFPRINT(request->url.path()),
 852                     AnyP::ProtocolType_str[request->http_ver.protocol],
 853                     request->http_ver.major, request->http_ver.minor);
 854         request->header.packInto(&str);
 855     }
 856
 857     str.append("\r\n", 2);
 858     /* - FTP stuff */
 859
 860     if (ftp.request) {
 861         str.appendf("FTP Request: %s\r\n", ftp.request);
 862         str.appendf("FTP Reply: %s\r\n", (ftp.reply? ftp.reply:"[none]"));
 863         str.append("FTP Msg: ", 9);
 864         wordlistCat(ftp.server_msg, &str);
 865         str.append("\r\n", 2);
 866     }
 867
 868     str.append("\r\n", 2);
 869     mb->appendf("&body=%s", rfc1738_escape_part(str.buf));
 870     str.clean();
 871     return 0;
 872 }
 873
 874 /// \ingroup ErrorPageInternal
 875 #define CVT_BUF_SZ 512
 876
 877 void
 878 ErrorState::compileLogformatCode(Build &build)
 879 {
 880     assert(LogformatMagic.cmp(build.input, LogformatMagic.length()) == 0);
 881
 882     try {
 883         const auto logformat = build.input + LogformatMagic.length();
 884
 885         // Logformat supports undocumented "external" encoding specifications
 886         // like [%>h] or "%<a". To preserve the possibility of extending
 887         // @Squid{} syntax to non-logformat sequences, we require logformat
 888         // sequences to start with '%'. This restriction does not limit
 889         // logformat quoting abilities. TODO: Deprecate "external" encoding?
 890         if (*logformat != '%')
 891             throw TexcHere("logformat expressions that do not start with % are not supported");
 892
 893         static MemBuf result;
 894         result.reset();
 895         const auto logformatLen = Format::AssembleOne(logformat, result, ale);
 896         assert(logformatLen > 0);
 897         const auto closure = logformat + logformatLen;
 898         if (*closure != '}')
 899             throw TexcHere("Missing closing brace (})");
 900         build.output.append(result.content(), result.contentSize());
 901         build.input = closure + 1;
 902         return;
 903     } catch (...) {
 904         noteBuildError("Bad @Squid{logformat} sequence", build.input);
 905     }
 906
 907     // we cannot recover reliably so stop interpreting the rest of input
 908     const auto remainingSize = strlen(build.input);
 909     build.output.append(build.input, remainingSize);
 910     build.input += remainingSize;
 911 }
 912
 913 void
 914 ErrorState::compileLegacyCode(Build &build)
 915 {
 916     static MemBuf mb;
 917     const char *p = nullptr;   /* takes priority over mb if set */
 918     int do_quote = 1;
 919     int no_urlescape = 0;       /* if true then item is NOT to be further URL-encoded */
 920     char ntoabuf[MAX_IPSTRLEN];
 921
 922     mb.reset();
 923
 924     const auto &building_deny_info_url = build.building_deny_info_url; // a change reduction hack
 925
 926     const auto letter = build.input[1];
 927
 928     switch (letter) {
 929
 930     case 'a':
 931 #if USE_AUTH
 932         if (request && request->auth_user_request)
 933             p = request->auth_user_request->username();
 934         if (!p)
 935 #endif
 936             p = "-";
 937         break;
 938
 939     case 'A':
 940         // TODO: When/if we get ALE here, pass it as well
 941         if (const auto addr = FindListeningPortAddress(request.getRaw(), nullptr))
 942             mb.appendf("%s", addr->toStr(ntoabuf, MAX_IPSTRLEN));
 943         else
 944             p = "-";
 945         break;
 946
 947     case 'b':
 948         mb.appendf("%u", getMyPort());
 949         break;
 950
 951     case 'B':
 952         if (building_deny_info_url) break;
 953         if (request) {
 954             const SBuf &tmp = Ftp::UrlWith2f(request.getRaw());
 955             mb.append(tmp.rawContent(), tmp.length());
 956         } else
 957             p = "[no URL]";
 958         break;
 959
 960     case 'c':
 961         if (building_deny_info_url) break;
 962         p = errorPageName(type);
 963         break;
 964
 965     case 'D':
 966         if (!build.allowRecursion)
 967             p = "%D";  // if recursion is not allowed, do not convert
 968         else if (detail) {
 969             auto rawDetail = detail->verbose(request);
 970             // XXX: Performance regression. c_str() reallocates
 971             const auto compiledDetail = compileBody(rawDetail.c_str(), false);
 972             mb.append(compiledDetail.rawContent(), compiledDetail.length());
 973             do_quote = 0;
 974         }
 975         if (!mb.contentSize())
 976             mb.append("[No Error Detail]", 17);
 977         break;
 978
 979     case 'e':
 980         mb.appendf("%d", xerrno);
 981         break;
 982
 983     case 'E':
 984         if (xerrno)
 985             mb.appendf("(%d) %s", xerrno, strerror(xerrno));
 986         else
 987             mb.append("[No Error]", 10);
 988         break;
 989
 990     case 'f':
 991         if (building_deny_info_url) break;
 992         /* FTP REQUEST LINE */
 993         if (ftp.request)
 994             p = ftp.request;
 995         else
 996             p = "nothing";
 997         break;
 998
 999     case 'F':
1000         if (building_deny_info_url) break;
1001         /* FTP REPLY LINE */
1002         if (ftp.reply)
1003             p = ftp.reply;
1004         else
1005             p = "nothing";
1006         break;
1007
1008     case 'g':
1009         if (building_deny_info_url) break;
1010         /* FTP SERVER RESPONSE */
1011         if (ftp.listing) {
1012             mb.append(ftp.listing->content(), ftp.listing->contentSize());
1013             do_quote = 0;
1014         } else if (ftp.server_msg) {
1015             wordlistCat(ftp.server_msg, &mb);
1016         }
1017         break;
1018
1019     case 'h':
1020         mb.appendf("%s", getMyHostname());
1021         break;
1022
1023     case 'H':
1024         if (request) {
1025             if (request->hier.host[0] != '\0') // if non-empty string.
1026                 p = request->hier.host;
1027             else
1028                 p = request->url.host();
1029         } else if (!building_deny_info_url)
1030             p = "[unknown host]";
1031         break;
1032
1033     case 'i':
1034         mb.appendf("%s", src_addr.toStr(ntoabuf,MAX_IPSTRLEN));
1035         break;
1036
1037     case 'I':
1038         if (request && request->hier.tcpServer)
1039             p = request->hier.tcpServer->remote.toStr(ntoabuf,MAX_IPSTRLEN);
1040         else if (!building_deny_info_url)
1041             p = "[unknown]";
1042         break;
1043
1044     case 'l':
1045         if (building_deny_info_url) break;
1046         mb.append(error_stylesheet.content(), error_stylesheet.contentSize());
1047         do_quote = 0;
1048         break;
1049
1050     case 'L':
1051         if (building_deny_info_url) break;
1052         if (Config.errHtmlText) {
1053             mb.appendf("%s", Config.errHtmlText);
1054             do_quote = 0;
1055         } else
1056             p = "[not available]";
1057         break;
1058
1059     case 'm':
1060         if (building_deny_info_url) break;
1061 #if USE_AUTH
1062         if (auth_user_request.getRaw())
1063             p = auth_user_request->denyMessage("[not available]");
1064         else
1065             p = "[not available]";
1066 #else
1067         p = "-";
1068 #endif
1069         break;
1070
1071     case 'M':
1072         if (request) {
1073             const SBuf &m = request->method.image();
1074             mb.append(m.rawContent(), m.length());
1075         } else if (!building_deny_info_url)
1076             p = "[unknown method]";
1077         break;
1078
1079     case 'O':
1080         if (!building_deny_info_url)
1081             do_quote = 0;
1082     /* [[fallthrough]] */
1083     case 'o':
1084         p = request ? request->extacl_message.termedBuf() : external_acl_message;
1085         if (!p && !building_deny_info_url)
1086             p = "[not available]";
1087         break;
1088
1089     case 'p':
1090         if (request) {
1091             mb.appendf("%u", request->url.port());
1092         } else if (!building_deny_info_url) {
1093             p = "[unknown port]";
1094         }
1095         break;
1096
1097     case 'P':
1098         if (request) {
1099             const SBuf &m = request->url.getScheme().image();
1100             mb.append(m.rawContent(), m.length());
1101         } else if (!building_deny_info_url) {
1102             p = "[unknown protocol]";
1103         }
1104         break;
1105
1106     case 'R':
1107         if (building_deny_info_url) {
1108             if (request != nullptr) {
1109                 const SBuf &tmp = request->url.path();
1110                 mb.append(tmp.rawContent(), tmp.length());
1111                 no_urlescape = 1;
1112             } else
1113                 p = "[no request]";
1114             break;
1115         }
1116         if (request) {
1117             mb.appendf(SQUIDSBUFPH " " SQUIDSBUFPH " %s/%d.%d\n",
1118                        SQUIDSBUFPRINT(request->method.image()),
1119                        SQUIDSBUFPRINT(request->url.path()),
1120                        AnyP::ProtocolType_str[request->http_ver.protocol],
1121                        request->http_ver.major, request->http_ver.minor);
1122             request->header.packInto(&mb, true); //hide authorization data
1123         } else if (request_hdrs) {
1124             p = request_hdrs;
1125         } else {
1126             p = "[no request]";
1127         }
1128         break;
1129
1130     case 's':
1131         /* for backward compat we make %s show the full URL. Drop this in some future release. */
1132         if (building_deny_info_url) {
1133             if (request) {
1134                 const SBuf &tmp = request->effectiveRequestUri();
1135                 mb.append(tmp.rawContent(), tmp.length());
1136             } else
1137                 p = url;
1138             debugs(0, DBG_CRITICAL, "WARNING: deny_info now accepts coded tags. Use %u to get the full URL instead of %s");
1139         } else
1140             p = visible_appname_string;
1141         break;
1142
1143     case 'S':
1144         if (building_deny_info_url) {
1145             p = visible_appname_string;
1146             break;
1147         }
1148         /* signature may contain %-escapes, recursion */
1149         if (page_id != ERR_SQUID_SIGNATURE) {
1150             const int saved_id = page_id;
1151             page_id = ERR_SQUID_SIGNATURE;
1152             const auto signature = buildBody();
1153             mb.append(signature.rawContent(), signature.length());
1154             page_id = saved_id;
1155             do_quote = 0;
1156         } else {
1157             /* wow, somebody put %S into ERR_SIGNATURE, stop recursion */
1158             p = "[%S]";
1159         }
1160         break;
1161
1162     case 't':
1163         mb.appendf("%s", Time::FormatHttpd(squid_curtime));
1164         break;
1165
1166     case 'T':
1167         mb.appendf("%s", Time::FormatRfc1123(squid_curtime));
1168         break;
1169
1170     case 'U':
1171         /* Using the fake-https version of absolute-URI so error pages see https:// */
1172         /* even when the url-path cannot be shown as more than '*' */
1173         if (request)
1174             p = urlCanonicalFakeHttps(request.getRaw());
1175         else if (url)
1176             p = url;
1177         else if (!building_deny_info_url)
1178             p = "[no URL]";
1179         break;
1180
1181     case 'u':
1182         if (request) {
1183             const SBuf &tmp = request->effectiveRequestUri();
1184             mb.append(tmp.rawContent(), tmp.length());
1185         } else if (url)
1186             p = url;
1187         else if (!building_deny_info_url)
1188             p = "[no URL]";
1189         break;
1190
1191     case 'w':
1192         if (Config.adminEmail)
1193             mb.appendf("%s", Config.adminEmail);
1194         else if (!building_deny_info_url)
1195             p = "[unknown]";
1196         break;
1197
1198     case 'W':
1199         if (building_deny_info_url) break;
1200         if (Config.adminEmail && Config.onoff.emailErrData)
1201             Dump(&mb);
1202         no_urlescape = 1;
1203         break;
1204
1205     case 'x':
1206         if (detail) {
1207             const auto brief = detail->brief();
1208             mb.append(brief.rawContent(), brief.length());
1209         } else if (!building_deny_info_url) {
1210             p = "[Unknown Error Code]";
1211         }
1212         break;
1213
1214     case 'z':
1215         if (building_deny_info_url) break;
1216         if (dnsError.size() > 0)
1217             p = dnsError.termedBuf();
1218         else if (ftp.cwd_msg)
1219             p = ftp.cwd_msg;
1220         else
1221             p = "[unknown]";
1222         break;
1223
1224     case 'Z':
1225         if (building_deny_info_url) break;
1226         if (err_msg)
1227             p = err_msg;
1228         else
1229             p = "[unknown]";
1230         break;
1231
1232     case '%':
1233         p = "%";
1234         break;
1235
1236     default:
1237         if (building_deny_info_url)
1238             bypassBuildErrorXXX("Unsupported deny_info %code", build.input);
1239         else if (letter != ';')
1240             bypassBuildErrorXXX("Unsupported error page %code", build.input);
1241         // else too many "font-size: 100%;" template errors to report
1242
1243         mb.append(build.input, 2);
1244         do_quote = 0;
1245         break;
1246     }
1247
1248     if (!p)
1249         p = mb.buf;     /* do not use mb after this assignment! */
1250
1251     assert(p);
1252
1253     debugs(4, 3, "%" << letter << " --> '" << p << "'" );
1254
1255     if (do_quote)
1256         p = html_quote(p);
1257
1258     if (building_deny_info_url && !no_urlescape)
1259         p = rfc1738_escape_part(p);
1260
1261     // TODO: Optimize by replacing mb with direct build.output usage.
1262     build.output.append(p, strlen(p));
1263     build.input += 2;
1264 }
1265
1266 void
1267 ErrorState::validate()
1268 {
1269     if (const auto urlTemplate = ErrorPage::IsDenyInfoUri(page_id)) {
1270         (void)compile(urlTemplate, true, true);
1271     } else {
1272         assert(page_id > ERR_NONE);
1273         assert(page_id < error_page_count);
1274         (void)compileBody(error_text[page_id], true);
1275     }
1276 }
1277
1278 HttpReply *
1279 ErrorState::BuildHttpReply()
1280 {
1281     if (response_)
1282         return response_.getRaw();
1283
1284     HttpReply *rep = new HttpReply;
1285     const char *name = errorPageName(page_id);
1286     /* no LMT for error pages; error pages expire immediately */
1287
1288     if (const auto urlTemplate = ErrorPage::IsDenyInfoUri(page_id)) {
1289         /* Redirection */
1290         Http::StatusCode status = Http::scFound;
1291         // Use configured 3xx reply status if set.
1292         if (name[0] == '3')
1293             status = httpStatus;
1294         else {
1295             // Use 307 for HTTP/1.1 non-GET/HEAD requests.
1296             if (request && request->method != Http::METHOD_GET && request->method != Http::METHOD_HEAD && request->http_ver >= Http::ProtocolVersion(1,1))
1297                 status = Http::scTemporaryRedirect;
1298         }
1299
1300         rep->setHeaders(status, nullptr, "text/html;charset=utf-8", 0, 0, -1);
1301
1302         if (request) {
1303             auto location = compile(urlTemplate, true, true);
1304             rep->header.putStr(Http::HdrType::LOCATION, location.c_str());
1305         }
1306
1307         httpHeaderPutStrf(&rep->header, Http::HdrType::X_SQUID_ERROR, "%d %s", httpStatus, "Access Denied");
1308     } else {
1309         const auto body = buildBody();
1310         rep->setHeaders(httpStatus, nullptr, "text/html;charset=utf-8", body.length(), 0, -1);
1311         /*
1312          * include some information for downstream caches. Implicit
1313          * replaceable content. This isn't quite sufficient. xerrno is not
1314          * necessarily meaningful to another system, so we really should
1315          * expand it. Additionally, we should identify ourselves. Someone
1316          * might want to know. Someone _will_ want to know OTOH, the first
1317          * X-CACHE-MISS entry should tell us who.
1318          */
1319         httpHeaderPutStrf(&rep->header, Http::HdrType::X_SQUID_ERROR, "%s %d", name, xerrno);
1320
1321 #if USE_ERR_LOCALES
1322         /*
1323          * If error page auto-negotiate is enabled in any way, send the Vary.
1324          * RFC 2616 section 13.6 and 14.44 says MAY and SHOULD do this.
1325          * We have even better reasons though:
1326          * see http://wiki.squid-cache.org/KnowledgeBase/VaryNotCaching
1327          */
1328         if (!Config.errorDirectory) {
1329             /* We 'negotiated' this ONLY from the Accept-Language. */
1330             rep->header.delById(Http::HdrType::VARY);
1331             rep->header.putStr(Http::HdrType::VARY, "Accept-Language");
1332         }
1333
1334         /* add the Content-Language header according to RFC section 14.12 */
1335         if (err_language) {
1336             rep->header.putStr(Http::HdrType::CONTENT_LANGUAGE, err_language);
1337         } else
1338 #endif /* USE_ERROR_LOCALES */
1339         {
1340             /* default templates are in English */
1341             /* language is known unless error_directory override used */
1342             if (!Config.errorDirectory)
1343                 rep->header.putStr(Http::HdrType::CONTENT_LANGUAGE, "en");
1344         }
1345
1346         rep->body.set(body);
1347     }
1348
1349     // Make sure error codes get back to the client side for logging and
1350     // error tracking.
1351     if (request) {
1352         if (detail)
1353             request->detailError(type, detail);
1354         else
1355             request->detailError(type, SysErrorDetail::NewIfAny(xerrno));
1356     }
1357
1358     return rep;
1359 }
1360
1361 SBuf
1362 ErrorState::buildBody()
1363 {
1364     assert(page_id > ERR_NONE && page_id < error_page_count);
1365
1366 #if USE_ERR_LOCALES
1367     /** error_directory option in squid.conf overrides translations.
1368      * Custom errors are always found either in error_directory or the templates directory.
1369      * Otherwise locate the Accept-Language header
1370      */
1371     if (!Config.errorDirectory && page_id < ERR_MAX) {
1372         if (err_language && err_language != Config.errorDefaultLanguage)
1373             safe_free(err_language);
1374
1375         ErrorPageFile localeTmpl(err_type_str[page_id], static_cast<err_type>(page_id));
1376         if (localeTmpl.loadFor(request.getRaw())) {
1377             inputLocation = localeTmpl.filename;
1378             assert(localeTmpl.language());
1379             err_language = xstrdup(localeTmpl.language());
1380             return compileBody(localeTmpl.text(), true);
1381         }
1382     }
1383 #endif /* USE_ERR_LOCALES */
1384
1385     /** \par
1386      * If client-specific error templates are not enabled or available.
1387      * fall back to the old style squid.conf settings.
1388      */
1389 #if USE_ERR_LOCALES
1390     if (!Config.errorDirectory)
1391         err_language = Config.errorDefaultLanguage;
1392 #endif
1393     debugs(4, 2, "No existing error page language negotiated for " << this << ". Using default error file.");
1394     return compileBody(error_text[page_id], true);
1395 }
1396
1397 SBuf
1398 ErrorState::compileBody(const char *input, bool allowRecursion)
1399 {
1400     return compile(input, false, allowRecursion);
1401 }
1402
1403 SBuf
1404 ErrorState::compile(const char *input, bool building_deny_info_url, bool allowRecursion)
1405 {
1406     assert(input);
1407
1408     Build build;
1409     build.building_deny_info_url = building_deny_info_url;
1410     build.allowRecursion = allowRecursion;
1411     build.input = input;
1412
1413     auto blockStart = build.input;
1414     while (const auto letter = *build.input) {
1415         if (letter == '%') {
1416             build.output.append(blockStart, build.input - blockStart);
1417             compileLegacyCode(build);
1418             blockStart = build.input;
1419         }
1420         else if (letter == '@' && LogformatMagic.cmp(build.input, LogformatMagic.length()) == 0) {
1421             build.output.append(blockStart, build.input - blockStart);
1422             compileLogformatCode(build);
1423             blockStart = build.input;
1424         } else {
1425             ++build.input;
1426         }
1427     }
1428     build.output.append(blockStart, build.input - blockStart);
1429     return build.output;
1430 }
1431
1432 /// react to a compile() error
1433 /// \param msg  description of what went wrong
1434 /// \param near  approximate start of the problematic input
1435 /// \param  forceBypass whether detection of this error was introduced late,
1436 /// after old configurations containing this error could have been
1437 /// successfully validated and deployed (i.e. the admin may not be
1438 /// able to fix this newly detected but old problem quickly)
1439 void
1440 ErrorState::noteBuildError_(const char *msg, const char *near, const bool forceBypass)
1441 {
1442     using ErrorPage::BuildErrorPrinter;
1443     const auto runtime = !starting_up;
1444     if (runtime || forceBypass) {
1445         // swallow this problem because the admin may not be (and/or the page
1446         // building code is not) ready to handle throwing consequences
1447
1448         static unsigned int seenErrors = 0;
1449         ++seenErrors;
1450
1451         const auto debugLevel =
1452             (seenErrors > 100) ? DBG_DATA:
1453             (starting_up || reconfiguring) ? DBG_CRITICAL:
1454             3; // most other errors have been reported as configuration errors
1455
1456         // Error fatality depends on the error context: Reconfiguration errors
1457         // are, like startup ones, DBG_CRITICAL but will never become FATAL.
1458         if (starting_up && seenErrors <= 10)
1459             debugs(4, debugLevel, "WARNING: The following configuration error will be fatal in future Squid versions");
1460
1461         debugs(4, debugLevel, "ERROR: " << BuildErrorPrinter(inputLocation, page_id, msg, near));
1462     } else {
1463         throw TexcHere(ToSBuf(BuildErrorPrinter(inputLocation, page_id, msg, near)));
1464     }
1465 }
1466
1467 /* ErrorPage::BuildErrorPrinter */
1468
1469 std::ostream &
1470 ErrorPage::BuildErrorPrinter::printLocation(std::ostream &os) const {
1471     if (!inputLocation.isEmpty())
1472         return os << inputLocation;
1473
1474     if (page_id < ERR_NONE || page_id >= error_page_count)
1475         return os << "[error page " << page_id << "]"; // should not happen
1476
1477     if (page_id < ERR_MAX)
1478         return os << err_type_str[page_id];
1479
1480     return os << "deny_info " << ErrorDynamicPages.at(page_id - ERR_MAX)->page_name;
1481 }
1482
1483 std::ostream &
1484 ErrorPage::BuildErrorPrinter::print(std::ostream &os) const {
1485     printLocation(os) << ": " << msg << " near ";
1486
1487     // TODO: Add support for prefix printing to Raw
1488     const size_t maxContextLength = 15; // plus "..."
1489     if (strlen(near) > maxContextLength) {
1490         os.write(near, maxContextLength);
1491         os << "...";
1492     } else {
1493         os << near;
1494     }
1495
1496     // XXX: We should not be converting (inner) exception to text if we are
1497     // going to throw again. See "add arbitrary (re)thrower-supplied details"
1498     // TODO in TextException.h for a long-term in-catcher solution.
1499     if (std::current_exception())
1500         os << "\n    additional info: " << CurrentException;
1501
1502     return os;
1503 }
1504
1505 /// add error page template to the global index
1506 static void
1507 ErrorPage::ImportStaticErrorText(const int page_id, const char *text, const SBuf &inputLocation)
1508 {
1509     assert(!error_text[page_id]);
1510     error_text[page_id] = xstrdup(text);
1511     ValidateStaticError(page_id, inputLocation);
1512 }
1513
1514 /// validate static error page
1515 static void
1516 ErrorPage::ValidateStaticError(const int page_id, const SBuf &inputLocation)
1517 {
1518     // Supplying nil ALE pointer limits validation to logformat %code
1519     // recognition by Format::Token::parse(). This is probably desirable
1520     // because actual %code assembly is slow and should not affect validation
1521     // when our ALE cannot have any real data (this code is not associated
1522     // with any real transaction).
1523     ErrorState anErr(err_type(page_id), Http::scNone, nullptr, nullptr);
1524     anErr.inputLocation = inputLocation;
1525     anErr.validate();
1526 }
1527
1528 std::ostream &
1529 operator <<(std::ostream &os, const ErrorState *err)
1530 {
1531     if (err)
1532         os << errorPageName(err->page_id);
1533     else
1534         os << "[none]";
1535     return os;
1536 }
1537