src/http/RegisteredHeaders.h

   1 /*
   2  * Copyright (C) 1996-2020 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 #ifndef SQUID_HTTP_REGISTEREDHEADERS_H
  10 #define SQUID_HTTP_REGISTEREDHEADERS_H
  11
  12 #include "base/LookupTable.h"
  13
  14 #include <iosfwd>
  15 #include <vector>
  16
  17 namespace Http
  18 {
  19 /// recognized or "known" header fields; and the RFC which defines them (or not)
  20 /// http://www.iana.org/assignments/message-headers/message-headers.xhtml
  21 enum HdrType {
  22     enumBegin_ = 0,                 // service value for WholeEnum iteration
  23     ACCEPT = enumBegin_,            /**< RFC 7231 */ /* MUST BE FIRST */
  24     ACCEPT_CHARSET,                 /**< RFC 7231 */
  25     ACCEPT_ENCODING,                /**< RFC 7231 */
  26     /*ACCEPT_FEATURES,*/            /* RFC 2295 */
  27     ACCEPT_LANGUAGE,                /**< RFC 7231 */
  28     ACCEPT_RANGES,                  /**< RFC 7233 */
  29     AGE,                            /**< RFC 7234 */
  30     ALLOW,                          /**< RFC 7231 */
  31     ALTERNATE_PROTOCOL,             /**< GFE custom header we may have to erase */
  32     AUTHENTICATION_INFO,            /**< RFC 2617 */
  33     AUTHORIZATION,                  /**< RFC 7235, 4559 */
  34     CACHE_CONTROL,                  /**< RFC 7234 */
  35     CDN_LOOP,                       /**< RFC 8586 */
  36     CONNECTION,                     /**< RFC 7230 */
  37     CONTENT_BASE,                   /**< obsoleted RFC 2068 */
  38     CONTENT_DISPOSITION,            /**< RFC 2183, 6266 */
  39     CONTENT_ENCODING,               /**< RFC 7231 */
  40     CONTENT_LANGUAGE,               /**< RFC 7231 */
  41     CONTENT_LENGTH,                 /**< RFC 7230 */
  42     CONTENT_LOCATION,               /**< RFC 7231 */
  43     CONTENT_MD5,                    /**< deprecated, RFC 2616 */
  44     CONTENT_RANGE,                  /**< RFC 7233 */
  45     CONTENT_TYPE,                   /**< RFC 7231 */
  46     COOKIE,                         /**< RFC 6265 header we may need to erase */
  47     COOKIE2,                        /**< obsolete RFC 2965 header we may need to erase */
  48     DATE,                           /**< RFC 7231 */
  49     /*DAV,*/                        /* RFC 2518 */
  50     /*DEPTH,*/                      /* RFC 2518 */
  51     /*DERIVED_FROM,*/               /* deprecated RFC 2068 */
  52     /*DESTINATION,*/                /* RFC 2518 */
  53     ETAG,                           /**< RFC 7232 */
  54     EXPECT,                         /**< RFC 7231 */
  55     EXPIRES,                        /**< RFC 7234 */
  56     FORWARDED,                      /**< RFC 7239 */
  57     FROM,                           /**< RFC 7231 */
  58     HOST,                           /**< RFC 7230 */
  59     HTTP2_SETTINGS,                 /**< RFC 7540 */
  60     /*IF,*/                         /* RFC 2518 */
  61     IF_MATCH,                       /**< RFC 7232 */
  62     IF_MODIFIED_SINCE,              /**< RFC 7232 */
  63     IF_NONE_MATCH,                  /**< RFC 7232 */
  64     IF_RANGE,                       /**< RFC 7233 */
  65     IF_UNMODIFIED_SINCE,            /**< RFC 7232 */
  66     KEEP_ALIVE,                     /**< obsoleted RFC 2068 header we may need to erase */
  67     KEY,                            /**< experimental RFC Draft draft-fielding-http-key-02 */
  68     LAST_MODIFIED,                  /**< RFC 7232 */
  69     LINK,                           /**< RFC 5988 */
  70     LOCATION,                       /**< RFC 7231 */
  71     /*LOCK_TOKEN,*/                 /* RFC 2518 */
  72     MAX_FORWARDS,                   /**< RFC 7231 */
  73     MIME_VERSION,                   /**< RFC 2045, 7231 */
  74     NEGOTIATE,                      /**< experimental RFC 2295. Why only this one from 2295? */
  75     /*OVERWRITE,*/                  /* RFC 2518 */
  76     ORIGIN,                         /* CORS Draft specification (see http://www.w3.org/TR/cors/) */
  77     PRAGMA,                         /**< RFC 7234 */
  78     PROXY_AUTHENTICATE,             /**< RFC 7235 */
  79     PROXY_AUTHENTICATION_INFO,      /**< RFC 2617 */
  80     PROXY_AUTHORIZATION,            /**< RFC 7235 */
  81     PROXY_CONNECTION,               /**< obsolete Netscape header we may need to erase. */
  82     PROXY_SUPPORT,                  /**< RFC 4559 */
  83     PUBLIC,                         /**<  RFC 2068 */
  84     RANGE,                          /**< RFC 7233 */
  85     REFERER,                        /**< RFC 7231 */
  86     REQUEST_RANGE,                  /**< some clients use this, sigh */
  87     RETRY_AFTER,                    /**< RFC 7231 */
  88     SERVER,                         /**< RFC 7231 */
  89     SET_COOKIE,                     /**< RFC 6265 header we may need to erase */
  90     SET_COOKIE2,                    /**< obsoleted RFC 2965 header we may need to erase */
  91     /*STATUS_URI,*/                 /* RFC 2518 */
  92     /*TCN,*/                        /* experimental RFC 2295 */
  93     TE,                             /**< RFC 7230 */
  94     /*TIMEOUT,*/                    /* RFC 2518 */
  95     TITLE,                          /* obsolete draft suggested header */
  96     TRAILER,                        /**< RFC 7230 */
  97     TRANSFER_ENCODING,              /**< RFC 7230 */
  98     TRANSLATE,                      /**< IIS custom header we may need to erase */
  99     UNLESS_MODIFIED_SINCE,          /**< IIS custom header we may need to erase */
 100     UPGRADE,                        /**< RFC 7230 */
 101     USER_AGENT,                     /**< RFC 7231 */
 102     /*VARIANT_VARY,*/               /* experimental RFC 2295 */
 103     VARY,                           /**< RFC 7231 */
 104     VIA,                            /**< RFC 7230 */
 105     WARNING,                        /**< RFC 7234 */
 106     WWW_AUTHENTICATE,               /**< RFC 7235, 4559 */
 107     X_CACHE,                        /**< Squid custom header */
 108     X_CACHE_LOOKUP,                 /**< Squid custom header. temporary hack that became de-facto. TODO remove */
 109     X_FORWARDED_FOR,                /**< obsolete Squid custom header, RFC 7239 */
 110     X_REQUEST_URI,                  /**< Squid custom header appended if ADD_X_REQUEST_URI is defined */
 111     X_SQUID_ERROR,                  /**< Squid custom header on generated error responses */
 112     HDR_X_ACCELERATOR_VARY,             /**< obsolete Squid custom header. */
 113     X_NEXT_SERVICES,                /**< Squid custom ICAP header */
 114     SURROGATE_CAPABILITY,           /**< Edge Side Includes (ESI) header */
 115     SURROGATE_CONTROL,              /**< Edge Side Includes (ESI) header */
 116     FRONT_END_HTTPS,                /**< MS Exchange custom header we may have to add */
 117     FTP_COMMAND,                    /**< Internal header for FTP command */
 118     FTP_ARGUMENTS,                  /**< Internal header for FTP command arguments */
 119     FTP_PRE,                        /**< Internal header containing leading FTP control response lines */
 120     FTP_STATUS,                     /**< Internal header for FTP reply status */
 121     FTP_REASON,                     /**< Internal header for FTP reply reason */
 122     OTHER,                          /**< internal tag value for "unknown" headers */
 123     BAD_HDR,                        /**< Invalid header */
 124     enumEnd_                        // internal tag for end-of-headers
 125 };
 126
 127 /** possible types for http header fields */
 128 enum class HdrFieldType {
 129     ftInvalid,  /**< to catch nasty errors with hdr_id<->fld_type clashes */
 130     ftInt,
 131     ftInt64,
 132     ftStr,
 133     ftDate_1123,
 134     ftETag,
 135     ftPCc,
 136     ftPContRange,
 137     ftPRange,
 138     ftPSc,
 139     ftDate_1123_or_ETag
 140 };
 141
 142 enum HdrKind {
 143     None = 0,
 144     ListHeader = 1,
 145     RequestHeader = 1 << 1,
 146     ReplyHeader = 1 << 2,
 147     HopByHopHeader = 1 << 3,
 148     Denied304Header = 1 << 4, //see comment in HttpReply.cc for meaning
 149     GeneralHeader = RequestHeader | ReplyHeader,
 150     EntityHeader = RequestHeader | ReplyHeader
 151 };
 152
 153 /* POD for HeaderTable */
 154 class HeaderTableRecord {
 155 public:
 156     HeaderTableRecord();
 157     HeaderTableRecord(const char *n);
 158     HeaderTableRecord(const char *, Http::HdrType, Http::HdrFieldType, int /* HdrKind */);
 159
 160 public:
 161     const char *name;
 162     Http::HdrType id;
 163     Http::HdrFieldType type;
 164     // flags set by constructor from HdrKind parameter
 165     bool list;       ///<header with field values defined as #(values) in HTTP/1.1
 166     bool request;    ///<header is a request header
 167     bool reply;      ///<header is a reply header
 168     bool hopbyhop;   ///<header is hop by hop
 169     bool denied304;  ///<header is not to be updated on receiving a 304 in cache revalidation (see HttpReply.cc)
 170 };
 171
 172 /** Class for looking up registered header definitions
 173  *
 174  * Look up HeaderTableRecord's by name or registered header ID.
 175  *
 176  * Actual records are defined in file RegisteredHeadersHash.gperf, which is
 177  * compiled using gperf to RegisteredHeadersHash.cci which is then included
 178  * in RegisteredHeaders.cc.
 179  */
 180 class HeaderLookupTable_t {
 181 public:
 182     HeaderLookupTable_t();
 183     /// look record type up by name (C-string and length)
 184     const HeaderTableRecord& lookup (const char *buf, const std::size_t len) const;
 185     /// look record type up by name (std::string)
 186     const HeaderTableRecord& lookup (const std::string &key) const {
 187         return lookup(key.data(), key.length());
 188     }
 189     /// look record type up by name (SBuf)
 190     const HeaderTableRecord& lookup (const SBuf &key) const {
 191         return lookup(key.rawContent(), key.length());
 192     }
 193     /// look record type up by header ID
 194     const HeaderTableRecord& lookup (Http::HdrType id) const {
 195         return *(idCache[static_cast<int>(id)]);
 196     }
 197
 198 private:
 199     void initCache();
 200     std::vector<const HeaderTableRecord *> idCache;
 201     static const HeaderTableRecord BadHdr; ///<used to signal "not found" from lookups
 202 };
 203 extern const HeaderLookupTable_t HeaderLookupTable;
 204
 205 /// match any known header type, including OTHER and BAD
 206 inline bool
 207 any_HdrType_enum_value (const Http::HdrType id)
 208 {
 209     return (id >= Http::HdrType::enumBegin_ && id < Http::HdrType::enumEnd_);
 210 }
 211
 212 /// match any valid header type, including OTHER but not BAD
 213 inline bool
 214 any_valid_header (const Http::HdrType id)
 215 {
 216     return (id >= Http::HdrType::ACCEPT && id < Http::HdrType::BAD_HDR);
 217 }
 218
 219 /// match any registered header type (headers squid knows how to handle),
 220 ///  thus excluding OTHER and BAD
 221 inline bool
 222 any_registered_header (const Http::HdrType id)
 223 {
 224     return (id >= Http::HdrType::ACCEPT && id < Http::HdrType::OTHER);
 225 }
 226
 227 }; /* namespace Http */
 228
 229 /* ostream output for Http::HdrType */
 230 std::ostream &
 231 operator<< (std::ostream&, Http::HdrType);
 232
 233 #endif /* SQUID_HTTP_REGISTEREDHEADERS_H */
 234