src/errorpage.h

   1 /*
   2  * DEBUG: section 04    Error Generation
   3  * AUTHOR: Duane Wessels
   4  *
   5  * SQUID Web Proxy Cache          http://www.squid-cache.org/
   6  * ----------------------------------------------------------
   7  *
   8  *  Squid is the result of efforts by numerous individuals from
   9  *  the Internet community; see the CONTRIBUTORS file for full
  10  *  details.   Many organizations have provided support for Squid's
  11  *  development; see the SPONSORS file for full details.  Squid is
  12  *  Copyrighted (C) 2001 by the Regents of the University of
  13  *  California; see the COPYRIGHT file for full details.  Squid
  14  *  incorporates software developed and/or copyrighted by other
  15  *  sources; see the CREDITS file for full details.
  16  *
  17  *  This program is free software; you can redistribute it and/or modify
  18  *  it under the terms of the GNU General Public License as published by
  19  *  the Free Software Foundation; either version 2 of the License, or
  20  *  (at your option) any later version.
  21  *
  22  *  This program is distributed in the hope that it will be useful,
  23  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  24  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  25  *  GNU General Public License for more details.
  26  *
  27  *  You should have received a copy of the GNU General Public License
  28  *  along with this program; if not, write to the Free Software
  29  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
  30  *
  31  * Copyright (c) 2003, Robert Collins <robertc@squid-cache.org>
  32  */
  33
  34 #ifndef   SQUID_ERRORPAGE_H
  35 #define   SQUID_ERRORPAGE_H
  36
  37 #include "squid-old.h"
  38 #if USE_AUTH
  39 #include "auth/UserRequest.h"
  40 #endif
  41 #include "cbdata.h"
  42 #include "comm/forward.h"
  43 #include "err_detail_type.h"
  44 #include "ip/Address.h"
  45 #include "MemBuf.h"
  46 #if USE_SSL
  47 #include "ssl/ErrorDetail.h"
  48 #endif
  49
  50 /**
  51  \defgroup ErrorPageAPI Error Pages API
  52  \ingroup Components
  53  \section ErrorPageStringCodes Error Page % codes for text insertion.
  54  *
  55  \verbatim
  56    a - User identity                            x
  57    B - URL with FTP %2f hack                    x
  58    c - Squid error code                         x
  59    d - seconds elapsed since request received   x
  60    D - Error details                            x
  61    e - errno                                    x
  62    E - strerror()                               x
  63    f - FTP request line                         x
  64    F - FTP reply line                           x
  65    g - FTP server message                       x
  66    h - cache hostname                           x
  67    H - server host name                         x
  68    i - client IP address                        x
  69    I - server IP address                        x
  70    l - HREF link for CSS stylesheet inclusion   x
  71    L - HREF link for more info/contact          x
  72    M - Request Method                           x
  73    m - Error message returned by auth helper    x
  74    o - Message returned external acl helper     x
  75    p - URL port #                               x
  76    P - Protocol                                 x
  77    R - Full HTTP Request                        x
  78    S - squid signature from ERR_SIGNATURE       x
  79    s - caching proxy software with version      x
  80    t - local time                               x
  81    T - UTC                                      x
  82    U - URL without password                     x
  83    u - URL with password                        x
  84    w - cachemgr email address                   x
  85    W - error data (to be included in the mailto links)
  86    x - error name                               x
  87    z - dns server error message                 x
  88    Z - Preformatted error message               x
  89  \endverbatim
  90  */
  91
  92 class HttpReply;
  93 class MemBuf;
  94
  95 /// \ingroup ErrorPageAPI
  96 class ErrorState
  97 {
  98 public:
  99     ErrorState(err_type type, http_status, HttpRequest * request);
 100     ErrorState(); // not implemented.
 101     ~ErrorState();
 102
 103     /**
 104      * Allocates and initializes an error response
 105      */
 106     HttpReply *BuildHttpReply(void);
 107
 108     /// set error type-specific detail code
 109     void detailError(int detailCode);
 110
 111 private:
 112     /**
 113      * Locates error page template to be used for this error
 114      * and constructs the HTML page content from it.
 115      */
 116     MemBuf *BuildContent(void);
 117
 118     /**
 119      * Convert the given template string into textual output
 120      *
 121      * \param text            The string to be converted
 122      * \param allowRecursion  Whether to convert codes which output may contain codes
 123      */
 124     MemBuf *ConvertText(const char *text, bool allowRecursion);
 125
 126     /**
 127      * Generates the Location: header value for a deny_info error page
 128      * to be used for this error.
 129      */
 130     void DenyInfoLocation(const char *name, HttpRequest *request, MemBuf &result);
 131
 132     /**
 133      * Map the Error page and deny_info template % codes into textual output.
 134      *
 135      * Several of the codes produce blocks of non-URL compatible results.
 136      * When processing the deny_info location URL they will be skipped.
 137      *
 138      * \param token                    The token following % which need to be converted
 139      * \param building_deny_info_url   Perform special deny_info actions, such as URL-encoding and token skipping.
 140      * \ allowRecursion   True if the codes which do recursions should converted
 141      */
 142     const char *Convert(char token, bool building_deny_info_url, bool allowRecursion);
 143
 144     /**
 145      * CacheManager / Debug dump of the ErrorState object.
 146      * Writes output into the given MemBuf.
 147      \retval 0 successful completion.
 148      */
 149     int Dump(MemBuf * mb);
 150
 151 public:
 152     err_type type;
 153     int page_id;
 154     char *err_language;
 155     http_status httpStatus;
 156 #if USE_AUTH
 157     Auth::UserRequest::Pointer auth_user_request;
 158 #endif
 159     HttpRequest *request;
 160     char *url;
 161     int xerrno;
 162     unsigned short port;
 163     String dnsError; ///< DNS lookup error message
 164     time_t ttl;
 165
 166     Ip::Address src_addr;
 167     char *redirect_url;
 168     ERCB *callback;
 169     void *callback_data;
 170
 171     struct {
 172         unsigned int flag_cbdata:1;
 173     } flags;
 174
 175     struct {
 176         wordlist *server_msg;
 177         char *request;
 178         char *reply;
 179         char *cwd_msg;
 180         MemBuf *listing;
 181     } ftp;
 182
 183     char *request_hdrs;
 184     char *err_msg; /* Preformatted error message from the cache */
 185
 186 #if USE_SSL
 187     Ssl::ErrorDetail *detail;
 188 #endif
 189     /// type-specific detail about the transaction error;
 190     /// overwrites xerrno; overwritten by detail, if any.
 191     int detailCode;
 192 private:
 193     CBDATA_CLASS2(ErrorState);
 194 };
 195
 196 /**
 197  \ingroup ErrorPageAPI
 198  *
 199  * This function finds the error messages formats, and stores
 200  * them in error_text[]
 201  *
 202  \par Global effects:
 203  *            error_text[] - is modified
 204  */
 205 SQUIDCEXTERN void errorInitialize(void);
 206
 207 /// \ingroup ErrorPageAPI
 208 SQUIDCEXTERN void errorClean(void);
 209
 210 /**
 211  * \ingroup ErrorPageAPI
 212  *
 213  * This function generates a error page from the info contained
 214  * by err and then sends it to the client.
 215  * The callback function errorSendComplete() is called after
 216  * the page has been written to the client (clientConn).
 217  * errorSendComplete() deallocates err.  We need to add
 218  * err to the cbdata because comm_write() requires it
 219  * for all callback data pointers.
 220  *
 221  \note normally errorSend() should only be called from
 222  *     routines in ssl.c and pass.c, where we don't have any
 223  *     StoreEntry's.  In client_side.c we must allocate a StoreEntry
 224  *     for errors and use errorAppendEntry() to account for
 225  *     persistent/pipeline connections.
 226  *
 227  \param clientConn  socket where page object is to be written
 228  \param err         This object is destroyed after use in this function.
 229  */
 230 SQUIDCEXTERN void errorSend(const Comm::ConnectionPointer &conn, ErrorState *err);
 231
 232 /**
 233  \ingroup ErrorPageAPI
 234  *
 235  * This function generates a error page from the info contained
 236  * by err and then stores the text in the specified store
 237  * entry.
 238  * This function should only be called by "server
 239  * side routines" which need to communicate errors to the
 240  * client side.  It should also be called from client_side.c
 241  * because we now support persistent connections, and
 242  * cannot assume that we can immediately write to the socket
 243  * for an error.
 244  *
 245  \param entry   ??
 246  \param err     This object is destroyed after use in this function.
 247  */
 248 SQUIDCEXTERN void errorAppendEntry(StoreEntry *entry, ErrorState *err);
 249
 250 /// \ingroup ErrorPageAPI
 251 SQUIDCEXTERN err_type errorReservePageId(const char *page_name);
 252
 253 SQUIDCEXTERN const char *errorPageName(int pageId); ///< error ID to string
 254
 255 /**
 256  \ingroup ErrorPageAPI
 257  *
 258  * loads text templates used for error pages and details;
 259  * supports translation of templates
 260  */
 261 class TemplateFile
 262 {
 263 public:
 264     TemplateFile(const char *name, const err_type code);
 265     virtual ~TemplateFile() {}
 266
 267     /// return true if the data loaded from disk without any problem
 268     bool loaded() const {return wasLoaded;}
 269
 270     /**
 271      * Load the page_name template from a file which  probably exist at:
 272      *  (a) admin specified custom directory (error_directory)
 273      *  (b) default language translation directory (error_default_language)
 274      *  (c) English sub-directory where errors should ALWAYS exist
 275      */
 276     bool loadDefault();
 277
 278     /**
 279      * Load an error template for a given HTTP request. This function examines the
 280      * Accept-Language header and select the first available template. If the default
 281      * template selected (eg because of a "Accept-Language: *"), or not available
 282      * template found this function return false.
 283      */
 284     bool loadFor(HttpRequest *request);
 285
 286     /**
 287      * Load the file given by "path". It uses the "parse()" method.
 288      * On success return true and sets the "defined" member
 289      */
 290     bool loadFromFile(const char *path);
 291
 292     /// The language used for the template
 293     const char *language() {return errLanguage.termedBuf();}
 294
 295     bool silent; ///< Whether to print error messages on cache.log file or not. It is user defined.
 296
 297 protected:
 298     /// Used to parse (if parsing required) the template data .
 299     virtual bool parse(const char *buf, int len, bool eof) = 0;
 300
 301     /**
 302      * Try to load the "page_name" template for a given language "lang"
 303      * from squid errors directory
 304      \return true on success false otherwise
 305      */
 306     bool tryLoadTemplate(const char *lang);
 307
 308     bool wasLoaded; ///< True if the template data read from disk without any problem
 309     String errLanguage; ///< The error language of the template.
 310     String templateName; ///< The name of the template
 311     err_type templateCode; ///< The internal code for this template.
 312 };
 313
 314 /**
 315  * Parses the Accept-Language header value and return one language item on
 316  * each call.
 317  * \param hdr is the Accept-Language header value
 318  * \param lang a buffer given by the user to store parsed language
 319  * \param langlen the length of the lang buffer
 320  * \param pos it is used to store the state of parsing. Must be "0" on first call
 321  * \return true on success, false otherwise
 322  */
 323 bool strHdrAcptLangGetItem(const String &hdr, char *lang, int langLen, size_t &pos);
 324 #endif /* SQUID_ERRORPAGE_H */