src/http/RegisteredHeaders.h

   1 /*
   2  * Copyright (C) 1996-2023 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_SRC_HTTP_REGISTEREDHEADERS_H
  10 #define SQUID_SRC_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 9111 */
  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 9111 */
  35     CACHE_STATUS,                   /**< draft-ietf-httpbis-cache-header */
  36     CDN_LOOP,                       /**< RFC 8586 */
  37     CONNECTION,                     /**< RFC 7230 */
  38     CONTENT_BASE,                   /**< obsoleted RFC 2068 */
  39     CONTENT_DISPOSITION,            /**< RFC 2183, 6266 */
  40     CONTENT_ENCODING,               /**< RFC 7231 */
  41     CONTENT_LANGUAGE,               /**< RFC 7231 */
  42     CONTENT_LENGTH,                 /**< RFC 7230 */
  43     CONTENT_LOCATION,               /**< RFC 7231 */
  44     CONTENT_MD5,                    /**< deprecated, RFC 2616 */
  45     CONTENT_RANGE,                  /**< RFC 7233 */
  46     CONTENT_TYPE,                   /**< RFC 7231 */
  47     COOKIE,                         /**< RFC 6265 header we may need to erase */
  48     COOKIE2,                        /**< obsolete RFC 2965 header we may need to erase */
  49     DATE,                           /**< RFC 7231 */
  50     /*DAV,*/                        /* RFC 2518 */
  51     /*DEPTH,*/                      /* RFC 2518 */
  52     /*DERIVED_FROM,*/               /* deprecated RFC 2068 */
  53     /*DESTINATION,*/                /* RFC 2518 */
  54     ETAG,                           /**< RFC 7232 */
  55     EXPECT,                         /**< RFC 7231 */
  56     EXPIRES,                        /**< RFC 9111 */
  57     FORWARDED,                      /**< RFC 7239 */
  58     FROM,                           /**< RFC 7231 */
  59     HOST,                           /**< RFC 7230 */
  60     /*HTTP2_SETTINGS,*/             /* obsolete RFC 7540 */
  61     /*IF,*/                         /* RFC 2518 */
  62     IF_MATCH,                       /**< RFC 7232 */
  63     IF_MODIFIED_SINCE,              /**< RFC 7232 */
  64     IF_NONE_MATCH,                  /**< RFC 7232 */
  65     IF_RANGE,                       /**< RFC 7233 */
  66     IF_UNMODIFIED_SINCE,            /**< RFC 7232 */
  67     KEEP_ALIVE,                     /**< obsoleted RFC 2068 header we may need to erase */
  68     KEY,                            /**< experimental RFC Draft draft-fielding-http-key-02 */
  69     LAST_MODIFIED,                  /**< RFC 7232 */
  70     LINK,                           /**< RFC 5988 */
  71     LOCATION,                       /**< RFC 7231 */
  72     /*LOCK_TOKEN,*/                 /* RFC 2518 */
  73     MAX_FORWARDS,                   /**< RFC 7231 */
  74     MIME_VERSION,                   /**< RFC 2045, 7231 */
  75     NEGOTIATE,                      /**< experimental RFC 2295. Why only this one from 2295? */
  76     /*OVERWRITE,*/                  /* RFC 2518 */
  77     ORIGIN,                         /* CORS Draft specification (see http://www.w3.org/TR/cors/) */
  78     PRAGMA,                         /**< deprecated RFC 7234 header */
  79     PRIORITY,                       /**< RFC 9218 */
  80     PROXY_AUTHENTICATE,             /**< RFC 7235 */
  81     PROXY_AUTHENTICATION_INFO,      /**< RFC 2617 */
  82     PROXY_AUTHORIZATION,            /**< RFC 7235 */
  83     PROXY_CONNECTION,               /**< obsolete Netscape header we may need to erase. */
  84     PROXY_SUPPORT,                  /**< RFC 4559 */
  85     PUBLIC,                         /**<  RFC 2068 */
  86     RANGE,                          /**< RFC 7233 */
  87     REFERER,                        /**< RFC 7231 */
  88     REQUEST_RANGE,                  /**< some clients use this, sigh */
  89     RETRY_AFTER,                    /**< RFC 7231 */
  90     SERVER,                         /**< RFC 7231 */
  91     SET_COOKIE,                     /**< RFC 6265 header we may need to erase */
  92     SET_COOKIE2,                    /**< obsoleted RFC 2965 header we may need to erase */
  93     /*STATUS_URI,*/                 /* RFC 2518 */
  94     /*TCN,*/                        /* experimental RFC 2295 */
  95     TE,                             /**< RFC 7230 */
  96     /*TIMEOUT,*/                    /* RFC 2518 */
  97     TITLE,                          /* obsolete draft suggested header */
  98     TRAILER,                        /**< RFC 7230 */
  99     TRANSFER_ENCODING,              /**< RFC 7230 */
 100     TRANSLATE,                      /**< IIS custom header we may need to erase */
 101     UNLESS_MODIFIED_SINCE,          /**< IIS custom header we may need to erase */
 102     UPGRADE,                        /**< RFC 7230 */
 103     USER_AGENT,                     /**< RFC 7231 */
 104     /*VARIANT_VARY,*/               /* experimental RFC 2295 */
 105     VARY,                           /**< RFC 7231 */
 106     VIA,                            /**< RFC 7230 */
 107     WWW_AUTHENTICATE,               /**< RFC 7235, 4559 */
 108     X_FORWARDED_FOR,                /**< obsolete Squid custom header, RFC 7239 */
 109     X_SQUID_ERROR,                  /**< Squid custom header on generated error responses */
 110     HDR_X_ACCELERATOR_VARY,             /**< obsolete Squid custom header. */
 111     X_NEXT_SERVICES,                /**< Squid custom ICAP header */
 112     SURROGATE_CAPABILITY,           /**< Edge Side Includes (ESI) header */
 113     SURROGATE_CONTROL,              /**< Edge Side Includes (ESI) header */
 114     FRONT_END_HTTPS,                /**< MS Exchange custom header we may have to add */
 115     FTP_COMMAND,                    /**< Internal header for FTP command */
 116     FTP_ARGUMENTS,                  /**< Internal header for FTP command arguments */
 117     FTP_PRE,                        /**< Internal header containing leading FTP control response lines */
 118     FTP_STATUS,                     /**< Internal header for FTP reply status */
 119     FTP_REASON,                     /**< Internal header for FTP reply reason */
 120     OTHER,                          /**< internal tag value for "unknown" headers */
 121     BAD_HDR,                        /**< Invalid header */
 122     enumEnd_                        // internal tag for end-of-headers
 123 };
 124
 125 /** possible types for http header fields */
 126 enum class HdrFieldType {
 127     ftInvalid,  /**< to catch nasty errors with hdr_id<->fld_type clashes */
 128     ftInt,
 129     ftInt64,
 130     ftStr,
 131     ftDate_1123,
 132     ftETag,
 133     ftPCc,
 134     ftPContRange,
 135     ftPRange,
 136     ftPSc,
 137     ftDate_1123_or_ETag
 138 };
 139
 140 enum HdrKind {
 141     None = 0,
 142     ListHeader = 1,
 143     RequestHeader = 1 << 1,
 144     ReplyHeader = 1 << 2,
 145     HopByHopHeader = 1 << 3,
 146     Denied304Header = 1 << 4, //see comment in HttpReply.cc for meaning
 147     GeneralHeader = RequestHeader | ReplyHeader,
 148     EntityHeader = RequestHeader | ReplyHeader
 149 };
 150
 151 /* POD for HeaderTable */
 152 class HeaderTableRecord {
 153 public:
 154     HeaderTableRecord() = default;
 155     HeaderTableRecord(const char *n);
 156     HeaderTableRecord(const char *, Http::HdrType, Http::HdrFieldType, int /* HdrKind */);
 157
 158     const char *name = "";
 159     Http::HdrType id = HdrType::BAD_HDR;
 160     Http::HdrFieldType type = HdrFieldType::ftInvalid;
 161     // flags set by constructor from HdrKind parameter
 162     bool list = false;; ///< header with field values defined as #(values) in HTTP/1.1
 163     bool request = false; ///< header is a request header
 164     bool reply = false; ///< header is a reply header
 165     bool hopbyhop = false; ///< header is hop by hop
 166     bool denied304 = false; ///< header is not to be updated on receiving a 304 in cache revalidation (see HttpReply.cc)
 167 };
 168
 169 /** Class for looking up registered header definitions
 170  *
 171  * Look up HeaderTableRecord's by name or registered header ID.
 172  *
 173  * Actual records are defined in file RegisteredHeadersHash.gperf, which is
 174  * compiled using gperf to RegisteredHeadersHash.cci which is then included
 175  * in RegisteredHeaders.cc.
 176  */
 177 class HeaderLookupTable_t {
 178 public:
 179     HeaderLookupTable_t();
 180     /// look record type up by name (C-string and length)
 181     const HeaderTableRecord& lookup (const char *buf, const std::size_t len) const;
 182     /// look record type up by name (std::string)
 183     const HeaderTableRecord& lookup (const std::string &key) const {
 184         return lookup(key.data(), key.length());
 185     }
 186     /// look record type up by name (SBuf)
 187     const HeaderTableRecord& lookup (const SBuf &key) const {
 188         return lookup(key.rawContent(), key.length());
 189     }
 190     /// look record type up by header ID
 191     const HeaderTableRecord& lookup (Http::HdrType id) const {
 192         return *(idCache[static_cast<int>(id)]);
 193     }
 194
 195 private:
 196     void initCache();
 197     std::vector<const HeaderTableRecord *> idCache;
 198     static const HeaderTableRecord BadHdr; ///<used to signal "not found" from lookups
 199 };
 200 extern const HeaderLookupTable_t HeaderLookupTable;
 201
 202 /// match any known header type, including OTHER and BAD
 203 inline bool
 204 any_HdrType_enum_value (const Http::HdrType id)
 205 {
 206     return (id >= Http::HdrType::enumBegin_ && id < Http::HdrType::enumEnd_);
 207 }
 208
 209 /// match any valid header type, including OTHER but not BAD
 210 inline bool
 211 any_valid_header (const Http::HdrType id)
 212 {
 213     return (id >= Http::HdrType::ACCEPT && id < Http::HdrType::BAD_HDR);
 214 }
 215
 216 /// match any registered header type (headers squid knows how to handle),
 217 ///  thus excluding OTHER and BAD
 218 inline bool
 219 any_registered_header (const Http::HdrType id)
 220 {
 221     return (id >= Http::HdrType::ACCEPT && id < Http::HdrType::OTHER);
 222 }
 223
 224 std::ostream &operator <<(std::ostream &, HdrType);
 225
 226 }; /* namespace Http */
 227
 228 #endif /* SQUID_SRC_HTTP_REGISTEREDHEADERS_H */
 229