net/base/sdch_dictionary.h

   1 // Copyright 2015 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef NET_BASE_SDCH_DICTIONARY_H_
   6 #define NET_BASE_SDCH_DICTIONARY_H_
   7
   8 #include <set>
   9 #include <string>
  10
  11 #include "base/memory/ref_counted.h"
  12 #include "base/memory/scoped_ptr.h"
  13 #include "base/time/time.h"
  14 #include "net/base/net_export.h"
  15 #include "net/base/sdch_problem_codes.h"
  16 #include "url/gurl.h"
  17
  18 namespace base {
  19 class Clock;
  20 class Value;
  21 }
  22
  23 namespace net {
  24
  25 // Contains all information for an SDCH dictionary.  This class is intended
  26 // to be used with a RefCountedData<> wrappers.  These dictionaries
  27 // are vended by SdchManager; see sdch_manager.h for details.
  28 class NET_EXPORT_PRIVATE SdchDictionary {
  29  public:
  30   // Construct a vc-diff usable dictionary from the dictionary_text starting
  31   // at the given offset. The supplied client_hash should be used to
  32   // advertise the dictionary's availability relative to the suppplied URL.
  33   SdchDictionary(const std::string& dictionary_text,
  34                  size_t offset,
  35                  const std::string& client_hash,
  36                  const std::string& server_hash,
  37                  const GURL& url,
  38                  const std::string& domain,
  39                  const std::string& path,
  40                  const base::Time& expiration,
  41                  const std::set<int>& ports);
  42
  43   ~SdchDictionary();
  44
  45   // Sdch filters can get our text to use in decoding compressed data.
  46   const std::string& text() const { return text_; }
  47
  48   const GURL& url() const { return url_; }
  49   const std::string& client_hash() const { return client_hash_; }
  50   const std::string& server_hash() const { return server_hash_; }
  51   const std::string& domain() const { return domain_; }
  52   const std::string& path() const { return path_; }
  53   const base::Time& expiration() const { return expiration_; }
  54   const std::set<int>& ports() const { return ports_; }
  55
  56   // Security methods to check if we can establish a new dictionary with the
  57   // given data, that arrived in response to get of dictionary_url.
  58   static SdchProblemCode CanSet(const std::string& domain,
  59                                 const std::string& path,
  60                                 const std::set<int>& ports,
  61                                 const GURL& dictionary_url);
  62
  63   // Security method to check if we can use a dictionary to decompress a
  64   // target that arrived with a reference to this dictionary.
  65   SdchProblemCode CanUse(const GURL& referring_url) const;
  66
  67   // Compare paths to see if they "match" for dictionary use.
  68   static bool PathMatch(const std::string& path,
  69                         const std::string& restriction);
  70
  71   // Is this dictionary expired?
  72   bool Expired() const;
  73
  74  private:
  75   friend class base::RefCountedData<SdchDictionary>;
  76
  77   // Private copy-constructor to support RefCountedData<>, which requires
  78   // that an object stored in it be either DefaultConstructible or
  79   // CopyConstructible
  80   SdchDictionary(const SdchDictionary& rhs);
  81
  82   // The actual text of the dictionary.
  83   std::string text_;
  84
  85   // Part of the hash of text_ that the client uses to advertise the fact that
  86   // it has a specific dictionary pre-cached.
  87   std::string client_hash_;
  88
  89   // Part of the hash of text_ that the server uses to identify the
  90   // dictionary it wants used for decoding.
  91   std::string server_hash_;
  92
  93   // The GURL that arrived with the text_ in a URL request to specify where
  94   // this dictionary may be used.
  95   const GURL url_;
  96
  97   // Metadate "headers" in before dictionary text contained the following:
  98   // Each dictionary payload consists of several headers, followed by the text
  99   // of the dictionary. The following are the known headers.
 100   const std::string domain_;
 101   const std::string path_;
 102   const base::Time expiration_;  // Implied by max-age.
 103   const std::set<int> ports_;
 104
 105   void operator=(const SdchDictionary&) = delete;
 106 };
 107
 108 }  // namespace net
 109
 110 #endif  // NET_BASE_SDCH_DICTIONARY_H_