src/errorpage.cc

   1 /*
   2  * Copyright (C) 1996-2019 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 "cache_cf.h"
  13 #include "clients/forward.h"
  14 #include "comm/Connection.h"
  15 #include "comm/Write.h"
  16 #include "err_detail_type.h"
  17 #include "errorpage.h"
  18 #include "fde.h"
  19 #include "fs_io.h"
  20 #include "html_quote.h"
  21 #include "HttpHeaderTools.h"
  22 #include "HttpReply.h"
  23 #include "HttpRequest.h"
  24 #include "MemBuf.h"
  25 #include "MemObject.h"
  26 #include "rfc1738.h"
  27 #include "SquidConfig.h"
  28 #include "Store.h"
  29 #include "tools.h"
  30 #include "wordlist.h"
  31 #if USE_AUTH
  32 #include "auth/UserRequest.h"
  33 #endif
  34 #include "SquidTime.h"
  35 #if USE_OPENSSL
  36 #include "ssl/ErrorDetailManager.h"
  37 #endif
  38
  39 /**
  40  \defgroup ErrorPageInternal Error Page Internals
  41  \ingroup ErrorPageAPI
  42  *
  43  \section ErrorPagesAbstract Abstract:
  44  *   These routines are used to generate error messages to be
  45  *   sent to clients.  The error type is used to select between
  46  *   the various message formats. (formats are stored in the
  47  *   Config.errorDirectory)
  48  */
  49
  50 #if !defined(DEFAULT_SQUID_ERROR_DIR)
  51 /** Where to look for errors if config path fails.
  52  \note Please use ./configure --datadir=/path instead of patching
  53  */
  54 #define DEFAULT_SQUID_ERROR_DIR   DEFAULT_SQUID_DATA_DIR"/errors"
  55 #endif
  56
  57 /// \ingroup ErrorPageInternal
  58 CBDATA_CLASS_INIT(ErrorState);
  59
  60 /* local types */
  61
  62 /// \ingroup ErrorPageInternal
  63 typedef struct {
  64     int id;
  65     char *page_name;
  66     Http::StatusCode page_redirect;
  67 } ErrorDynamicPageInfo;
  68
  69 /* local constant and vars */
  70
  71 /**
  72  \ingroup ErrorPageInternal
  73  *
  74  \note  hard coded error messages are not appended with %S
  75  *      automagically to give you more control on the format
  76  */
  77 static const struct {
  78     int type;           /* and page_id */
  79     const char *text;
  80 }
  81
  82 error_hard_text[] = {
  83
  84     {
  85         ERR_SQUID_SIGNATURE,
  86         "\n<br>\n"
  87         "<hr>\n"
  88         "<div id=\"footer\">\n"
  89         "Generated %T by %h (%s)\n"
  90         "</div>\n"
  91         "</body></html>\n"
  92     },
  93     {
  94         TCP_RESET,
  95         "reset"
  96     }
  97 };
  98
  99 /// \ingroup ErrorPageInternal
 100 static std::vector<ErrorDynamicPageInfo *> ErrorDynamicPages;
 101
 102 /* local prototypes */
 103
 104 /// \ingroup ErrorPageInternal
 105 static const int error_hard_text_count = sizeof(error_hard_text) / sizeof(*error_hard_text);
 106
 107 /// \ingroup ErrorPageInternal
 108 static char **error_text = NULL;
 109
 110 /// \ingroup ErrorPageInternal
 111 static int error_page_count = 0;
 112
 113 /// \ingroup ErrorPageInternal
 114 static MemBuf error_stylesheet;
 115
 116 static const char *errorFindHardText(err_type type);
 117 static ErrorDynamicPageInfo *errorDynamicPageInfoCreate(int id, const char *page_name);
 118 static void errorDynamicPageInfoDestroy(ErrorDynamicPageInfo * info);
 119 static IOCB errorSendComplete;
 120
 121 /// \ingroup ErrorPageInternal
 122 /// manages an error page template
 123 class ErrorPageFile: public TemplateFile
 124 {
 125 public:
 126     ErrorPageFile(const char *name, const err_type code) : TemplateFile(name,code) {textBuf.init();}
 127
 128     /// The template text data read from disk
 129     const char *text() { return textBuf.content(); }
 130
 131 private:
 132     /// stores the data read from disk to a local buffer
 133     virtual bool parse(const char *buf, int len, bool) {
 134         if (len)
 135             textBuf.append(buf, len);
 136         return true;
 137     }
 138
 139     MemBuf textBuf; ///< A buffer to store the error page
 140 };
 141
 142 /// \ingroup ErrorPageInternal
 143 err_type &operator++ (err_type &anErr)
 144 {
 145     int tmp = (int)anErr;
 146     anErr = (err_type)(++tmp);
 147     return anErr;
 148 }
 149
 150 /// \ingroup ErrorPageInternal
 151 int operator - (err_type const &anErr, err_type const &anErr2)
 152 {
 153     return (int)anErr - (int)anErr2;
 154 }
 155
 156 void
 157 errorInitialize(void)
 158 {
 159     err_type i;
 160     const char *text;
 161     error_page_count = ERR_MAX + ErrorDynamicPages.size();
 162     error_text = static_cast<char **>(xcalloc(error_page_count, sizeof(char *)));
 163
 164     for (i = ERR_NONE, ++i; i < error_page_count; ++i) {
 165         safe_free(error_text[i]);
 166
 167         if ((text = errorFindHardText(i))) {
 168             /**\par
 169              * Index any hard-coded error text into defaults.
 170              */
 171             error_text[i] = xstrdup(text);
 172
 173         } else if (i < ERR_MAX) {
 174             /**\par
 175              * Index precompiled fixed template files from one of two sources:
 176              *  (a) default language translation directory (error_default_language)
 177              *  (b) admin specified custom directory (error_directory)
 178              */
 179             ErrorPageFile errTmpl(err_type_str[i], i);
 180             error_text[i] = errTmpl.loadDefault() ? xstrdup(errTmpl.text()) : NULL;
 181         } else {
 182             /** \par
 183              * Index any unknown file names used by deny_info.
 184              */
 185             ErrorDynamicPageInfo *info = ErrorDynamicPages.at(i - ERR_MAX);
 186             assert(info && info->id == i && info->page_name);
 187
 188             const char *pg = info->page_name;
 189             if (info->page_redirect != Http::scNone)
 190                 pg = info->page_name +4;
 191
 192             if (strchr(pg, ':') == NULL) {
 193                 /** But only if they are not redirection URL. */
 194                 ErrorPageFile errTmpl(pg, ERR_MAX);
 195                 error_text[i] = errTmpl.loadDefault() ? xstrdup(errTmpl.text()) : NULL;
 196             }
 197         }
 198     }
 199
 200     error_stylesheet.reset();
 201
 202     // look for and load stylesheet into global MemBuf for it.
 203     if (Config.errorStylesheet) {
 204         ErrorPageFile tmpl("StylesSheet", ERR_MAX);
 205         tmpl.loadFromFile(Config.errorStylesheet);
 206         error_stylesheet.appendf("%s",tmpl.text());
 207     }
 208
 209 #if USE_OPENSSL
 210     Ssl::errorDetailInitialize();
 211 #endif
 212 }
 213
 214 void
 215 errorClean(void)
 216 {
 217     if (error_text) {
 218         int i;
 219
 220         for (i = ERR_NONE + 1; i < error_page_count; ++i)
 221             safe_free(error_text[i]);
 222
 223         safe_free(error_text);
 224     }
 225
 226     while (!ErrorDynamicPages.empty()) {
 227         errorDynamicPageInfoDestroy(ErrorDynamicPages.back());
 228         ErrorDynamicPages.pop_back();
 229     }
 230
 231     error_page_count = 0;
 232
 233 #if USE_OPENSSL
 234     Ssl::errorDetailClean();
 235 #endif
 236 }
 237
 238 /// \ingroup ErrorPageInternal
 239 static const char *
 240 errorFindHardText(err_type type)
 241 {
 242     int i;
 243
 244     for (i = 0; i < error_hard_text_count; ++i)
 245         if (error_hard_text[i].type == type)
 246             return error_hard_text[i].text;
 247
 248     return NULL;
 249 }
 250
 251 TemplateFile::TemplateFile(const char *name, const err_type code): silent(false), wasLoaded(false), templateName(name), templateCode(code)
 252 {
 253     assert(name);
 254 }
 255
 256 bool
 257 TemplateFile::loadDefault()
 258 {
 259     if (loaded()) // already loaded?
 260         return true;
 261
 262     /** test error_directory configured location */
 263     if (Config.errorDirectory) {
 264         char path[MAXPATHLEN];
 265         snprintf(path, sizeof(path), "%s/%s", Config.errorDirectory, templateName.termedBuf());
 266         loadFromFile(path);
 267     }
 268
 269 #if USE_ERR_LOCALES
 270     /** test error_default_language location */
 271     if (!loaded() && Config.errorDefaultLanguage) {
 272         if (!tryLoadTemplate(Config.errorDefaultLanguage)) {
 273             debugs(1, (templateCode < TCP_RESET ? DBG_CRITICAL : 3), "Unable to load default error language files. Reset to backups.");
 274         }
 275     }
 276 #endif
 277
 278     /* test default location if failed (templates == English translation base templates) */
 279     if (!loaded()) {
 280         tryLoadTemplate("templates");
 281     }
 282
 283     /* giving up if failed */
 284     if (!loaded()) {
 285         debugs(1, (templateCode < TCP_RESET ? DBG_CRITICAL : 3), "WARNING: failed to find or read error text file " << templateName);
 286         parse("Internal Error: Missing Template ", 33, '\0');
 287         parse(templateName.termedBuf(), templateName.size(), '\0');
 288     }
 289
 290     return true;
 291 }
 292
 293 bool
 294 TemplateFile::tryLoadTemplate(const char *lang)
 295 {
 296     assert(lang);
 297
 298     char path[MAXPATHLEN];
 299     /* TODO: prep the directory path string to prevent snprintf ... */
 300     snprintf(path, sizeof(path), "%s/%s/%s",
 301              DEFAULT_SQUID_ERROR_DIR, lang, templateName.termedBuf());
 302     path[MAXPATHLEN-1] = '\0';
 303
 304     if (loadFromFile(path))
 305         return true;
 306
 307 #if HAVE_GLOB
 308     if ( strlen(lang) == 2) {
 309         /* TODO glob the error directory for sub-dirs matching: <tag> '-*'   */
 310         /* use first result. */
 311         debugs(4,2, HERE << "wildcard fallback errors not coded yet.");
 312     }
 313 #endif
 314
 315     return false;
 316 }
 317
 318 bool
 319 TemplateFile::loadFromFile(const char *path)
 320 {
 321     int fd;
 322     char buf[4096];
 323     ssize_t len;
 324
 325     if (loaded()) // already loaded?
 326         return true;
 327
 328     fd = file_open(path, O_RDONLY | O_TEXT);
 329
 330     if (fd < 0) {
 331         /* with dynamic locale negotiation we may see some failures before a success. */
 332         if (!silent && templateCode < TCP_RESET) {
 333             int xerrno = errno;
 334             debugs(4, DBG_CRITICAL, "ERROR: loading file '" << path << "': " << xstrerr(xerrno));
 335         }
 336         wasLoaded = false;
 337         return wasLoaded;
 338     }
 339
 340     while ((len = FD_READ_METHOD(fd, buf, sizeof(buf))) > 0) {
 341         if (!parse(buf, len, false)) {
 342             debugs(4, DBG_CRITICAL, "ERROR: parsing error in template file: " << path);
 343             wasLoaded = false;
 344             return wasLoaded;
 345         }
 346     }
 347     parse(buf, 0, true);
 348
 349     if (len < 0) {
 350         int xerrno = errno;
 351         debugs(4, DBG_CRITICAL, MYNAME << "ERROR: failed to fully read: '" << path << "': " << xstrerr(xerrno));
 352     }
 353
 354     file_close(fd);
 355
 356     wasLoaded = true;
 357     return wasLoaded;
 358 }
 359
 360 bool strHdrAcptLangGetItem(const String &hdr, char *lang, int langLen, size_t &pos)
 361 {
 362     while (pos < hdr.size()) {
 363
 364         /* skip any initial whitespace. */
 365         while (pos < hdr.size() && xisspace(hdr[pos]))
 366             ++pos;
 367
 368         /*
 369          * Header value format:
 370          *  - sequence of whitespace delimited tags
 371          *  - each tag may suffix with ';'.* which we can ignore.
 372          *  - IFF a tag contains only two characters we can wildcard ANY translations matching: <it> '-'? .*
 373          *    with preference given to an exact match.
 374          */
 375         bool invalid_byte = false;
 376         char *dt = lang;
 377         while (pos < hdr.size() && hdr[pos] != ';' && hdr[pos] != ',' && !xisspace(hdr[pos]) && dt < (lang + (langLen -1)) ) {
 378             if (!invalid_byte) {
 379 #if USE_HTTP_VIOLATIONS
 380                 // if accepting violations we may as well accept some broken browsers
 381                 //  which may send us the right code, wrong ISO formatting.
 382                 if (hdr[pos] == '_')
 383                     *dt = '-';
 384                 else
 385 #endif
 386                     *dt = xtolower(hdr[pos]);
 387                 // valid codes only contain A-Z, hyphen (-) and *
 388                 if (*dt != '-' && *dt != '*' && (*dt < 'a' || *dt > 'z') )
 389                     invalid_byte = true;
 390                 else
 391                     ++dt; // move to next destination byte.
 392             }
 393             ++pos;
 394         }
 395         *dt = '\0'; // nul-terminated the filename content string before system use.
 396
 397         // if we terminated the tag on garbage or ';' we need to skip to the next ',' or end of header.
 398         while (pos < hdr.size() && hdr[pos] != ',')
 399             ++pos;
 400
 401         if (pos < hdr.size() && hdr[pos] == ',')
 402             ++pos;
 403
 404         debugs(4, 9, "STATE: lang=" << lang << ", pos=" << pos << ", buf='" << ((pos < hdr.size()) ? hdr.substr(pos,hdr.size()) : "") << "'");
 405
 406         /* if we found anything we might use, try it. */
 407         if (*lang != '\0' && !invalid_byte)
 408             return true;
 409     }
 410     return false;
 411 }
 412
 413 bool
 414 TemplateFile::loadFor(const HttpRequest *request)
 415 {
 416     String hdr;
 417
 418 #if USE_ERR_LOCALES
 419     if (loaded()) // already loaded?
 420         return true;
 421
 422     if (!request || !request->header.getList(Http::HdrType::ACCEPT_LANGUAGE, &hdr))
 423         return false;
 424
 425     char lang[256];
 426     size_t pos = 0; // current parsing position in header string
 427
 428     debugs(4, 6, HERE << "Testing Header: '" << hdr << "'");
 429
 430     while ( strHdrAcptLangGetItem(hdr, lang, 256, pos) ) {
 431
 432         /* wildcard uses the configured default language */
 433         if (lang[0] == '*' && lang[1] == '\0') {
 434             debugs(4, 6, HERE << "Found language '" << lang << "'. Using configured default.");
 435             return false;
 436         }
 437
 438         debugs(4, 6, HERE << "Found language '" << lang << "', testing for available template");
 439
 440         if (tryLoadTemplate(lang)) {
 441             /* store the language we found for the Content-Language reply header */
 442             errLanguage = lang;
 443             break;
 444         } else if (Config.errorLogMissingLanguages) {
 445             debugs(4, DBG_IMPORTANT, "WARNING: Error Pages Missing Language: " << lang);
 446         }
 447     }
 448 #endif
 449
 450     return loaded();
 451 }
 452
 453 /// \ingroup ErrorPageInternal
 454 static ErrorDynamicPageInfo *
 455 errorDynamicPageInfoCreate(int id, const char *page_name)
 456 {
 457     ErrorDynamicPageInfo *info = new ErrorDynamicPageInfo;
 458     info->id = id;
 459     info->page_name = xstrdup(page_name);
 460     info->page_redirect = static_cast<Http::StatusCode>(atoi(page_name));
 461
 462     /* WARNING on redirection status:
 463      * 2xx are permitted, but not documented officially.
 464      * - might be useful for serving static files (PAC etc) in special cases
 465      * 3xx require a URL suitable for Location: header.
 466      * - the current design does not allow for a Location: URI as well as a local file template
 467      *   although this possibility is explicitly permitted in the specs.
 468      * 4xx-5xx require a local file template.
 469      * - sending Location: on these codes with no body is invalid by the specs.
 470      * - current result is Squid crashing or XSS problems as dynamic deny_info load random disk files.
 471      * - a future redesign of the file loading may result in loading remote objects sent inline as local body.
 472      */
 473     if (info->page_redirect == Http::scNone)
 474         ; // special case okay.
 475     else if (info->page_redirect < 200 || info->page_redirect > 599) {
 476         // out of range
 477         debugs(0, DBG_CRITICAL, "FATAL: status " << info->page_redirect << " is not valid on '" << page_name << "'");
 478         self_destruct();
 479     } else if ( /* >= 200 && */ info->page_redirect < 300 && strchr(&(page_name[4]), ':')) {
 480         // 2xx require a local template file
 481         debugs(0, DBG_CRITICAL, "FATAL: status " << info->page_redirect << " requires a template on '" << page_name << "'");
 482         self_destruct();
 483     } else if (info->page_redirect >= 300 && info->page_redirect <= 399 && !strchr(&(page_name[4]), ':')) {
 484         // 3xx require an absolute URL
 485         debugs(0, DBG_CRITICAL, "FATAL: status " << info->page_redirect << " requires a URL on '" << page_name << "'");
 486         self_destruct();
 487     } else if (info->page_redirect >= 400 /* && <= 599 */ && strchr(&(page_name[4]), ':')) {
 488         // 4xx/5xx require a local template file
 489         debugs(0, DBG_CRITICAL, "FATAL: status " << info->page_redirect << " requires a template on '" << page_name << "'");
 490         self_destruct();
 491     }
 492     // else okay.
 493
 494     return info;
 495 }
 496
 497 /// \ingroup ErrorPageInternal
 498 static void
 499 errorDynamicPageInfoDestroy(ErrorDynamicPageInfo * info)
 500 {
 501     assert(info);
 502     safe_free(info->page_name);
 503     delete info;
 504 }
 505
 506 /// \ingroup ErrorPageInternal
 507 static int
 508 errorPageId(const char *page_name)
 509 {
 510     for (int i = 0; i < ERR_MAX; ++i) {
 511         if (strcmp(err_type_str[i], page_name) == 0)
 512             return i;
 513     }
 514
 515     for (size_t j = 0; j < ErrorDynamicPages.size(); ++j) {
 516         if (strcmp(ErrorDynamicPages[j]->page_name, page_name) == 0)
 517             return j + ERR_MAX;
 518     }
 519
 520     return ERR_NONE;
 521 }
 522
 523 err_type
 524 errorReservePageId(const char *page_name)
 525 {
 526     ErrorDynamicPageInfo *info;
 527     int id = errorPageId(page_name);
 528
 529     if (id == ERR_NONE) {
 530         info = errorDynamicPageInfoCreate(ERR_MAX + ErrorDynamicPages.size(), page_name);
 531         ErrorDynamicPages.push_back(info);
 532         id = info->id;
 533     }
 534
 535     return (err_type)id;
 536 }
 537
 538 /// \ingroup ErrorPageInternal
 539 const char *
 540 errorPageName(int pageId)
 541 {
 542     if (pageId >= ERR_NONE && pageId < ERR_MAX)     /* common case */
 543         return err_type_str[pageId];
 544
 545     if (pageId >= ERR_MAX && pageId - ERR_MAX < (ssize_t)ErrorDynamicPages.size())
 546         return ErrorDynamicPages[pageId - ERR_MAX]->page_name;
 547
 548     return "ERR_UNKNOWN";   /* should not happen */
 549 }
 550
 551 ErrorState *
 552 ErrorState::NewForwarding(err_type type, HttpRequestPointer &request)
 553 {
 554     const Http::StatusCode status = (request && request->flags.needValidation) ?
 555                                     Http::scGatewayTimeout : Http::scServiceUnavailable;
 556     return new ErrorState(type, status, request.getRaw());
 557 }
 558
 559 ErrorState::ErrorState(err_type t, Http::StatusCode status, HttpRequest * req) :
 560     type(t),
 561     page_id(t),
 562     httpStatus(status),
 563     callback(nullptr)
 564 {
 565     if (page_id >= ERR_MAX && ErrorDynamicPages[page_id - ERR_MAX]->page_redirect != Http::scNone)
 566         httpStatus = ErrorDynamicPages[page_id - ERR_MAX]->page_redirect;
 567
 568     if (req) {
 569         request = req;
 570         src_addr = req->client_addr;
 571     }
 572 }
 573
 574 void
 575 errorAppendEntry(StoreEntry * entry, ErrorState * err)
 576 {
 577     assert(entry->mem_obj != NULL);
 578     assert (entry->isEmpty());
 579     debugs(4, 4, "Creating an error page for entry " << entry <<
 580            " with errorstate " << err <<
 581            " page id " << err->page_id);
 582
 583     if (entry->store_status != STORE_PENDING) {
 584         debugs(4, 2, "Skipping error page due to store_status: " << entry->store_status);
 585         /*
 586          * If the entry is not STORE_PENDING, then no clients
 587          * care about it, and we don't need to generate an
 588          * error message
 589          */
 590         assert(EBIT_TEST(entry->flags, ENTRY_ABORTED));
 591         assert(entry->mem_obj->nclients == 0);
 592         delete err;
 593         return;
 594     }
 595
 596     if (err->page_id == TCP_RESET) {
 597         if (err->request) {
 598             debugs(4, 2, "RSTing this reply");
 599             err->request->flags.resetTcp = true;
 600         }
 601     }
 602
 603     entry->storeErrorResponse(err->BuildHttpReply());
 604     delete err;
 605 }
 606
 607 void
 608 errorSend(const Comm::ConnectionPointer &conn, ErrorState * err)
 609 {
 610     debugs(4, 3, conn << ", err=" << err);
 611     assert(Comm::IsConnOpen(conn));
 612
 613     HttpReplyPointer rep(err->BuildHttpReply());
 614
 615     MemBuf *mb = rep->pack();
 616     AsyncCall::Pointer call = commCbCall(78, 5, "errorSendComplete",
 617                                          CommIoCbPtrFun(&errorSendComplete, err));
 618     Comm::Write(conn, mb, call);
 619     delete mb;
 620 }
 621
 622 /**
 623  \ingroup ErrorPageAPI
 624  *
 625  * Called by commHandleWrite() after data has been written
 626  * to the client socket.
 627  *
 628  \note If there is a callback, the callback is responsible for
 629  *     closing the FD, otherwise we do it ourselves.
 630  */
 631 static void
 632 errorSendComplete(const Comm::ConnectionPointer &conn, char *, size_t size, Comm::Flag errflag, int, void *data)
 633 {
 634     ErrorState *err = static_cast<ErrorState *>(data);
 635     debugs(4, 3, HERE << conn << ", size=" << size);
 636
 637     if (errflag != Comm::ERR_CLOSING) {
 638         if (err->callback) {
 639             debugs(4, 3, "errorSendComplete: callback");
 640             err->callback(conn->fd, err->callback_data, size);
 641         } else {
 642             debugs(4, 3, "errorSendComplete: comm_close");
 643             conn->close();
 644         }
 645     }
 646
 647     delete err;
 648 }
 649
 650 ErrorState::~ErrorState()
 651 {
 652     safe_free(redirect_url);
 653     safe_free(url);
 654     safe_free(request_hdrs);
 655     wordlistDestroy(&ftp.server_msg);
 656     safe_free(ftp.request);
 657     safe_free(ftp.reply);
 658     safe_free(err_msg);
 659 #if USE_ERR_LOCALES
 660     if (err_language != Config.errorDefaultLanguage)
 661 #endif
 662         safe_free(err_language);
 663 #if USE_OPENSSL
 664     delete detail;
 665 #endif
 666 }
 667
 668 int
 669 ErrorState::Dump(MemBuf * mb)
 670 {
 671     MemBuf str;
 672     char ntoabuf[MAX_IPSTRLEN];
 673
 674     str.reset();
 675     /* email subject line */
 676     str.appendf("CacheErrorInfo - %s", errorPageName(type));
 677     mb->appendf("?subject=%s", rfc1738_escape_part(str.buf));
 678     str.reset();
 679     /* email body */
 680     str.appendf("CacheHost: %s\r\n", getMyHostname());
 681     /* - Err Msgs */
 682     str.appendf("ErrPage: %s\r\n", errorPageName(type));
 683
 684     if (xerrno) {
 685         str.appendf("Err: (%d) %s\r\n", xerrno, strerror(xerrno));
 686     } else {
 687         str.append("Err: [none]\r\n", 13);
 688     }
 689 #if USE_AUTH
 690     if (auth_user_request.getRaw() && auth_user_request->denyMessage())
 691         str.appendf("Auth ErrMsg: %s\r\n", auth_user_request->denyMessage());
 692 #endif
 693     if (dnsError.size() > 0)
 694         str.appendf("DNS ErrMsg: %s\r\n", dnsError.termedBuf());
 695
 696     /* - TimeStamp */
 697     str.appendf("TimeStamp: %s\r\n\r\n", mkrfc1123(squid_curtime));
 698
 699     /* - IP stuff */
 700     str.appendf("ClientIP: %s\r\n", src_addr.toStr(ntoabuf,MAX_IPSTRLEN));
 701
 702     if (request && request->hier.host[0] != '\0') {
 703         str.appendf("ServerIP: %s\r\n", request->hier.host);
 704     }
 705
 706     str.append("\r\n", 2);
 707     /* - HTTP stuff */
 708     str.append("HTTP Request:\r\n", 15);
 709     if (request) {
 710         str.appendf(SQUIDSBUFPH " " SQUIDSBUFPH " %s/%d.%d\n",
 711                     SQUIDSBUFPRINT(request->method.image()),
 712                     SQUIDSBUFPRINT(request->url.path()),
 713                     AnyP::ProtocolType_str[request->http_ver.protocol],
 714                     request->http_ver.major, request->http_ver.minor);
 715         request->header.packInto(&str);
 716     }
 717
 718     str.append("\r\n", 2);
 719     /* - FTP stuff */
 720
 721     if (ftp.request) {
 722         str.appendf("FTP Request: %s\r\n", ftp.request);
 723         str.appendf("FTP Reply: %s\r\n", (ftp.reply? ftp.reply:"[none]"));
 724         str.append("FTP Msg: ", 9);
 725         wordlistCat(ftp.server_msg, &str);
 726         str.append("\r\n", 2);
 727     }
 728
 729     str.append("\r\n", 2);
 730     mb->appendf("&body=%s", rfc1738_escape_part(str.buf));
 731     str.clean();
 732     return 0;
 733 }
 734
 735 /// \ingroup ErrorPageInternal
 736 #define CVT_BUF_SZ 512
 737
 738 const char *
 739 ErrorState::Convert(char token, bool building_deny_info_url, bool allowRecursion)
 740 {
 741     static MemBuf mb;
 742     const char *p = NULL;   /* takes priority over mb if set */
 743     int do_quote = 1;
 744     int no_urlescape = 0;       /* if true then item is NOT to be further URL-encoded */
 745     char ntoabuf[MAX_IPSTRLEN];
 746
 747     mb.reset();
 748
 749     switch (token) {
 750
 751     case 'a':
 752 #if USE_AUTH
 753         if (request && request->auth_user_request)
 754             p = request->auth_user_request->username();
 755         if (!p)
 756 #endif
 757             p = "-";
 758         break;
 759
 760     case 'A':
 761         // TODO: When/if we get ALE here, pass it as well
 762         if (const auto addr = FindListeningPortAddress(request.getRaw(), nullptr))
 763             mb.appendf("%s", addr->toStr(ntoabuf, MAX_IPSTRLEN));
 764         else
 765             p = "-";
 766         break;
 767
 768     case 'b':
 769         mb.appendf("%u", getMyPort());
 770         break;
 771
 772     case 'B':
 773         if (building_deny_info_url) break;
 774         if (request) {
 775             const SBuf &tmp = Ftp::UrlWith2f(request.getRaw());
 776             mb.append(tmp.rawContent(), tmp.length());
 777         } else
 778             p = "[no URL]";
 779         break;
 780
 781     case 'c':
 782         if (building_deny_info_url) break;
 783         p = errorPageName(type);
 784         break;
 785
 786     case 'D':
 787         if (!allowRecursion)
 788             p = "%D";  // if recursion is not allowed, do not convert
 789 #if USE_OPENSSL
 790         // currently only SSL error details implemented
 791         else if (detail) {
 792             detail->useRequest(request.getRaw());
 793             const String &errDetail = detail->toString();
 794             if (errDetail.size() > 0) {
 795                 MemBuf *detail_mb  = ConvertText(errDetail.termedBuf(), false);
 796                 mb.append(detail_mb->content(), detail_mb->contentSize());
 797                 delete detail_mb;
 798                 do_quote = 0;
 799             }
 800         }
 801 #endif
 802         if (!mb.contentSize())
 803             mb.append("[No Error Detail]", 17);
 804         break;
 805
 806     case 'e':
 807         mb.appendf("%d", xerrno);
 808         break;
 809
 810     case 'E':
 811         if (xerrno)
 812             mb.appendf("(%d) %s", xerrno, strerror(xerrno));
 813         else
 814             mb.append("[No Error]", 10);
 815         break;
 816
 817     case 'f':
 818         if (building_deny_info_url) break;
 819         /* FTP REQUEST LINE */
 820         if (ftp.request)
 821             p = ftp.request;
 822         else
 823             p = "nothing";
 824         break;
 825
 826     case 'F':
 827         if (building_deny_info_url) break;
 828         /* FTP REPLY LINE */
 829         if (ftp.reply)
 830             p = ftp.reply;
 831         else
 832             p = "nothing";
 833         break;
 834
 835     case 'g':
 836         if (building_deny_info_url) break;
 837         /* FTP SERVER RESPONSE */
 838         if (ftp.listing) {
 839             mb.append(ftp.listing->content(), ftp.listing->contentSize());
 840             do_quote = 0;
 841         } else if (ftp.server_msg) {
 842             wordlistCat(ftp.server_msg, &mb);
 843         }
 844         break;
 845
 846     case 'h':
 847         mb.appendf("%s", getMyHostname());
 848         break;
 849
 850     case 'H':
 851         if (request) {
 852             if (request->hier.host[0] != '\0') // if non-empty string.
 853                 p = request->hier.host;
 854             else
 855                 p = request->url.host();
 856         } else if (!building_deny_info_url)
 857             p = "[unknown host]";
 858         break;
 859
 860     case 'i':
 861         mb.appendf("%s", src_addr.toStr(ntoabuf,MAX_IPSTRLEN));
 862         break;
 863
 864     case 'I':
 865         if (request && request->hier.tcpServer)
 866             p = request->hier.tcpServer->remote.toStr(ntoabuf,MAX_IPSTRLEN);
 867         else if (!building_deny_info_url)
 868             p = "[unknown]";
 869         break;
 870
 871     case 'l':
 872         if (building_deny_info_url) break;
 873         mb.append(error_stylesheet.content(), error_stylesheet.contentSize());
 874         do_quote = 0;
 875         break;
 876
 877     case 'L':
 878         if (building_deny_info_url) break;
 879         if (Config.errHtmlText) {
 880             mb.appendf("%s", Config.errHtmlText);
 881             do_quote = 0;
 882         } else
 883             p = "[not available]";
 884         break;
 885
 886     case 'm':
 887         if (building_deny_info_url) break;
 888 #if USE_AUTH
 889         if (auth_user_request.getRaw())
 890             p = auth_user_request->denyMessage("[not available]");
 891         else
 892             p = "[not available]";
 893 #else
 894         p = "-";
 895 #endif
 896         break;
 897
 898     case 'M':
 899         if (request) {
 900             const SBuf &m = request->method.image();
 901             mb.append(m.rawContent(), m.length());
 902         } else if (!building_deny_info_url)
 903             p = "[unknown method]";
 904         break;
 905
 906     case 'O':
 907         if (!building_deny_info_url)
 908             do_quote = 0;
 909     case 'o':
 910         p = request ? request->extacl_message.termedBuf() : external_acl_message;
 911         if (!p && !building_deny_info_url)
 912             p = "[not available]";
 913         break;
 914
 915     case 'p':
 916         if (request) {
 917             mb.appendf("%u", request->url.port());
 918         } else if (!building_deny_info_url) {
 919             p = "[unknown port]";
 920         }
 921         break;
 922
 923     case 'P':
 924         if (request) {
 925             const SBuf &m = request->url.getScheme().image();
 926             mb.append(m.rawContent(), m.length());
 927         } else if (!building_deny_info_url) {
 928             p = "[unknown protocol]";
 929         }
 930         break;
 931
 932     case 'R':
 933         if (building_deny_info_url) {
 934             if (request != NULL) {
 935                 const SBuf &tmp = request->url.path();
 936                 mb.append(tmp.rawContent(), tmp.length());
 937                 no_urlescape = 1;
 938             } else
 939                 p = "[no request]";
 940             break;
 941         }
 942         if (request) {
 943             mb.appendf(SQUIDSBUFPH " " SQUIDSBUFPH " %s/%d.%d\n",
 944                        SQUIDSBUFPRINT(request->method.image()),
 945                        SQUIDSBUFPRINT(request->url.path()),
 946                        AnyP::ProtocolType_str[request->http_ver.protocol],
 947                        request->http_ver.major, request->http_ver.minor);
 948             request->header.packInto(&mb, true); //hide authorization data
 949         } else if (request_hdrs) {
 950             p = request_hdrs;
 951         } else {
 952             p = "[no request]";
 953         }
 954         break;
 955
 956     case 's':
 957         /* for backward compat we make %s show the full URL. Drop this in some future release. */
 958         if (building_deny_info_url) {
 959             if (request) {
 960                 const SBuf &tmp = request->effectiveRequestUri();
 961                 mb.append(tmp.rawContent(), tmp.length());
 962             } else
 963                 p = url;
 964             debugs(0, DBG_CRITICAL, "WARNING: deny_info now accepts coded tags. Use %u to get the full URL instead of %s");
 965         } else
 966             p = visible_appname_string;
 967         break;
 968
 969     case 'S':
 970         if (building_deny_info_url) {
 971             p = visible_appname_string;
 972             break;
 973         }
 974         /* signature may contain %-escapes, recursion */
 975         if (page_id != ERR_SQUID_SIGNATURE) {
 976             const int saved_id = page_id;
 977             page_id = ERR_SQUID_SIGNATURE;
 978             MemBuf *sign_mb = BuildContent();
 979             mb.append(sign_mb->content(), sign_mb->contentSize());
 980             sign_mb->clean();
 981             delete sign_mb;
 982             page_id = saved_id;
 983             do_quote = 0;
 984         } else {
 985             /* wow, somebody put %S into ERR_SIGNATURE, stop recursion */
 986             p = "[%S]";
 987         }
 988         break;
 989
 990     case 't':
 991         mb.appendf("%s", Time::FormatHttpd(squid_curtime));
 992         break;
 993
 994     case 'T':
 995         mb.appendf("%s", mkrfc1123(squid_curtime));
 996         break;
 997
 998     case 'U':
 999         /* Using the fake-https version of absolute-URI so error pages see https:// */
1000         /* even when the url-path cannot be shown as more than '*' */
1001         if (request)
1002             p = urlCanonicalFakeHttps(request.getRaw());
1003         else if (url)
1004             p = url;
1005         else if (!building_deny_info_url)
1006             p = "[no URL]";
1007         break;
1008
1009     case 'u':
1010         if (request) {
1011             const SBuf &tmp = request->effectiveRequestUri();
1012             mb.append(tmp.rawContent(), tmp.length());
1013         } else if (url)
1014             p = url;
1015         else if (!building_deny_info_url)
1016             p = "[no URL]";
1017         break;
1018
1019     case 'w':
1020         if (Config.adminEmail)
1021             mb.appendf("%s", Config.adminEmail);
1022         else if (!building_deny_info_url)
1023             p = "[unknown]";
1024         break;
1025
1026     case 'W':
1027         if (building_deny_info_url) break;
1028         if (Config.adminEmail && Config.onoff.emailErrData)
1029             Dump(&mb);
1030         no_urlescape = 1;
1031         break;
1032
1033     case 'x':
1034 #if USE_OPENSSL
1035         if (detail)
1036             mb.appendf("%s", detail->errorName());
1037         else
1038 #endif
1039             if (!building_deny_info_url)
1040                 p = "[Unknown Error Code]";
1041         break;
1042
1043     case 'z':
1044         if (building_deny_info_url) break;
1045         if (dnsError.size() > 0)
1046             p = dnsError.termedBuf();
1047         else if (ftp.cwd_msg)
1048             p = ftp.cwd_msg;
1049         else
1050             p = "[unknown]";
1051         break;
1052
1053     case 'Z':
1054         if (building_deny_info_url) break;
1055         if (err_msg)
1056             p = err_msg;
1057         else
1058             p = "[unknown]";
1059         break;
1060
1061     case '%':
1062         p = "%";
1063         break;
1064
1065     default:
1066         mb.appendf("%%%c", token);
1067         do_quote = 0;
1068         break;
1069     }
1070
1071     if (!p)
1072         p = mb.buf;     /* do not use mb after this assignment! */
1073
1074     assert(p);
1075
1076     debugs(4, 3, "errorConvert: %%" << token << " --> '" << p << "'" );
1077
1078     if (do_quote)
1079         p = html_quote(p);
1080
1081     if (building_deny_info_url && !no_urlescape)
1082         p = rfc1738_escape_part(p);
1083
1084     return p;
1085 }
1086
1087 void
1088 ErrorState::DenyInfoLocation(const char *name, HttpRequest *, MemBuf &result)
1089 {
1090     char const *m = name;
1091     char const *p = m;
1092     char const *t;
1093
1094     if (m[0] == '3')
1095         m += 4; // skip "3xx:"
1096
1097     while ((p = strchr(m, '%'))) {
1098         result.append(m, p - m);       /* copy */
1099         t = Convert(*++p, true, true);       /* convert */
1100         result.appendf("%s", t);        /* copy */
1101         m = p + 1;                     /* advance */
1102     }
1103
1104     if (*m)
1105         result.appendf("%s", m);        /* copy tail */
1106
1107     assert((size_t)result.contentSize() == strlen(result.content()));
1108 }
1109
1110 HttpReply *
1111 ErrorState::BuildHttpReply()
1112 {
1113     HttpReply *rep = new HttpReply;
1114     const char *name = errorPageName(page_id);
1115     /* no LMT for error pages; error pages expire immediately */
1116
1117     if (name[0] == '3' || (name[0] != '2' && name[0] != '4' && name[0] != '5' && strchr(name, ':'))) {
1118         /* Redirection */
1119         Http::StatusCode status = Http::scFound;
1120         // Use configured 3xx reply status if set.
1121         if (name[0] == '3')
1122             status = httpStatus;
1123         else {
1124             // Use 307 for HTTP/1.1 non-GET/HEAD requests.
1125             if (request && request->method != Http::METHOD_GET && request->method != Http::METHOD_HEAD && request->http_ver >= Http::ProtocolVersion(1,1))
1126                 status = Http::scTemporaryRedirect;
1127         }
1128
1129         rep->setHeaders(status, NULL, "text/html;charset=utf-8", 0, 0, -1);
1130
1131         if (request) {
1132             MemBuf redirect_location;
1133             redirect_location.init();
1134             DenyInfoLocation(name, request.getRaw(), redirect_location);
1135             httpHeaderPutStrf(&rep->header, Http::HdrType::LOCATION, "%s", redirect_location.content() );
1136         }
1137
1138         httpHeaderPutStrf(&rep->header, Http::HdrType::X_SQUID_ERROR, "%d %s", httpStatus, "Access Denied");
1139     } else {
1140         MemBuf *content = BuildContent();
1141         rep->setHeaders(httpStatus, NULL, "text/html;charset=utf-8", content->contentSize(), 0, -1);
1142         /*
1143          * include some information for downstream caches. Implicit
1144          * replaceable content. This isn't quite sufficient. xerrno is not
1145          * necessarily meaningful to another system, so we really should
1146          * expand it. Additionally, we should identify ourselves. Someone
1147          * might want to know. Someone _will_ want to know OTOH, the first
1148          * X-CACHE-MISS entry should tell us who.
1149          */
1150         httpHeaderPutStrf(&rep->header, Http::HdrType::X_SQUID_ERROR, "%s %d", name, xerrno);
1151
1152 #if USE_ERR_LOCALES
1153         /*
1154          * If error page auto-negotiate is enabled in any way, send the Vary.
1155          * RFC 2616 section 13.6 and 14.44 says MAY and SHOULD do this.
1156          * We have even better reasons though:
1157          * see http://wiki.squid-cache.org/KnowledgeBase/VaryNotCaching
1158          */
1159         if (!Config.errorDirectory) {
1160             /* We 'negotiated' this ONLY from the Accept-Language. */
1161             rep->header.delById(Http::HdrType::VARY);
1162             rep->header.putStr(Http::HdrType::VARY, "Accept-Language");
1163         }
1164
1165         /* add the Content-Language header according to RFC section 14.12 */
1166         if (err_language) {
1167             rep->header.putStr(Http::HdrType::CONTENT_LANGUAGE, err_language);
1168         } else
1169 #endif /* USE_ERROR_LOCALES */
1170         {
1171             /* default templates are in English */
1172             /* language is known unless error_directory override used */
1173             if (!Config.errorDirectory)
1174                 rep->header.putStr(Http::HdrType::CONTENT_LANGUAGE, "en");
1175         }
1176
1177         rep->body.setMb(content);
1178         /* do not memBufClean() or delete the content, it was absorbed by httpBody */
1179     }
1180
1181     // Make sure error codes get back to the client side for logging and
1182     // error tracking.
1183     if (request) {
1184         int edc = ERR_DETAIL_NONE; // error detail code
1185 #if USE_OPENSSL
1186         if (detail)
1187             edc = detail->errorNo();
1188         else
1189 #endif
1190             if (detailCode)
1191                 edc = detailCode;
1192             else
1193                 edc = xerrno;
1194         request->detailError(type, edc);
1195     }
1196
1197     return rep;
1198 }
1199
1200 MemBuf *
1201 ErrorState::BuildContent()
1202 {
1203     const char *m = NULL;
1204
1205     assert(page_id > ERR_NONE && page_id < error_page_count);
1206
1207 #if USE_ERR_LOCALES
1208     ErrorPageFile *localeTmpl = NULL;
1209
1210     /** error_directory option in squid.conf overrides translations.
1211      * Custom errors are always found either in error_directory or the templates directory.
1212      * Otherwise locate the Accept-Language header
1213      */
1214     if (!Config.errorDirectory && page_id < ERR_MAX) {
1215         if (err_language && err_language != Config.errorDefaultLanguage)
1216             safe_free(err_language);
1217
1218         localeTmpl = new ErrorPageFile(err_type_str[page_id], static_cast<err_type>(page_id));
1219         if (localeTmpl->loadFor(request.getRaw())) {
1220             m = localeTmpl->text();
1221             assert(localeTmpl->language());
1222             err_language = xstrdup(localeTmpl->language());
1223         }
1224     }
1225 #endif /* USE_ERR_LOCALES */
1226
1227     /** \par
1228      * If client-specific error templates are not enabled or available.
1229      * fall back to the old style squid.conf settings.
1230      */
1231     if (!m) {
1232         m = error_text[page_id];
1233 #if USE_ERR_LOCALES
1234         if (!Config.errorDirectory)
1235             err_language = Config.errorDefaultLanguage;
1236 #endif
1237         debugs(4, 2, HERE << "No existing error page language negotiated for " << errorPageName(page_id) << ". Using default error file.");
1238     }
1239
1240     MemBuf *result = ConvertText(m, true);
1241 #if USE_ERR_LOCALES
1242     if (localeTmpl)
1243         delete localeTmpl;
1244 #endif
1245     return result;
1246 }
1247
1248 MemBuf *ErrorState::ConvertText(const char *text, bool allowRecursion)
1249 {
1250     MemBuf *content = new MemBuf;
1251     const char *p;
1252     const char *m = text;
1253     assert(m);
1254     content->init();
1255
1256     while ((p = strchr(m, '%'))) {
1257         content->append(m, p - m);  /* copy */
1258         const char *t = Convert(*++p, false, allowRecursion);   /* convert */
1259         content->appendf("%s", t);   /* copy */
1260         m = p + 1;          /* advance */
1261     }
1262
1263     if (*m)
1264         content->appendf("%s", m);   /* copy tail */
1265
1266     content->terminate();
1267
1268     assert((size_t)content->contentSize() == strlen(content->content()));
1269
1270     return content;
1271 }
1272