netwerk/protocol/http/nsHttpResponseHead.h

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #ifndef nsHttpResponseHead_h__
   7 #define nsHttpResponseHead_h__
   8
   9 #include "nsHttpHeaderArray.h"
  10 #include "nsHttp.h"
  11 #include "nsString.h"
  12 #include "mozilla/RecursiveMutex.h"
  13
  14 #ifdef Status
  15 /* Xlib headers insist on this for some reason... Nuke it because
  16    it'll override our member name */
  17 typedef Status __StatusTmp;
  18 #  undef Status
  19 typedef __StatusTmp Status;
  20 #endif
  21
  22 class nsIHttpHeaderVisitor;
  23
  24 // This needs to be forward declared here so we can include only this header
  25 // without also including PHttpChannelParams.h
  26 namespace IPC {
  27 template <typename>
  28 struct ParamTraits;
  29 }  // namespace IPC
  30
  31 namespace mozilla {
  32 namespace net {
  33
  34 //-----------------------------------------------------------------------------
  35 // nsHttpResponseHead represents the status line and headers from an HTTP
  36 // response.
  37 //-----------------------------------------------------------------------------
  38
  39 class nsHttpResponseHead {
  40  public:
  41   nsHttpResponseHead() = default;
  42
  43   nsHttpResponseHead(const nsHttpResponseHead& aOther);
  44   nsHttpResponseHead& operator=(const nsHttpResponseHead& aOther);
  45
  46   void Enter() const MOZ_CAPABILITY_ACQUIRE(mRecursiveMutex) {
  47     mRecursiveMutex.Lock();
  48   }
  49   void Exit() const MOZ_CAPABILITY_RELEASE(mRecursiveMutex) {
  50     mRecursiveMutex.Unlock();
  51   }
  52   void AssertMutexOwned() const { mRecursiveMutex.AssertCurrentThreadIn(); }
  53
  54   HttpVersion Version();
  55   uint16_t Status() const;
  56   void StatusText(nsACString& aStatusText);
  57   int64_t ContentLength();
  58   void ContentType(nsACString& aContentType) const;
  59   void ContentCharset(nsACString& aContentCharset);
  60   bool Public();
  61   bool Private();
  62   bool NoStore();
  63   bool NoCache();
  64   bool Immutable();
  65   /**
  66    * Full length of the entity. For byte-range requests, this may be larger
  67    * than ContentLength(), which will only represent the requested part of the
  68    * entity.
  69    */
  70   int64_t TotalEntitySize();
  71
  72   [[nodiscard]] nsresult SetHeader(const nsACString& h, const nsACString& v,
  73                                    bool m = false);
  74   [[nodiscard]] nsresult SetHeader(const nsHttpAtom& h, const nsACString& v,
  75                                    bool m = false);
  76   [[nodiscard]] nsresult GetHeader(const nsHttpAtom& h, nsACString& v) const;
  77   void ClearHeader(const nsHttpAtom& h);
  78   void ClearHeaders();
  79   bool HasHeaderValue(const nsHttpAtom& h, const char* v);
  80   bool HasHeader(const nsHttpAtom& h) const;
  81
  82   void SetContentType(const nsACString& s);
  83   void SetContentCharset(const nsACString& s);
  84   void SetContentLength(int64_t);
  85
  86   // write out the response status line and headers as a single text block,
  87   // optionally pruning out transient headers (ie. headers that only make
  88   // sense the first time the response is handled).
  89   // Both functions append to the string supplied string.
  90   void Flatten(nsACString&, bool pruneTransients);
  91   void FlattenNetworkOriginalHeaders(nsACString& buf);
  92
  93   // The next 2 functions parse flattened response head and original net
  94   // headers. They are used when we are reading an entry from the cache.
  95   //
  96   // To keep proper order of the original headers we MUST call
  97   // ParseCachedOriginalHeaders FIRST and then ParseCachedHead.
  98   //
  99   // block must be null terminated.
 100   [[nodiscard]] nsresult ParseCachedHead(const char* block);
 101   [[nodiscard]] nsresult ParseCachedOriginalHeaders(char* block);
 102
 103   // parse the status line.
 104   nsresult ParseStatusLine(const nsACString& line);
 105
 106   // parse a header line.
 107   [[nodiscard]] nsresult ParseHeaderLine(const nsACString& line);
 108
 109   // cache validation support methods
 110   [[nodiscard]] nsresult ComputeFreshnessLifetime(uint32_t*);
 111   [[nodiscard]] nsresult ComputeCurrentAge(uint32_t now, uint32_t requestTime,
 112                                            uint32_t* result);
 113   bool MustValidate();
 114   bool MustValidateIfExpired();
 115
 116   // return true if the response contains a valid Cache-control:
 117   // stale-while-revalidate and |now| is less than or equal |expiration +
 118   // stale-while-revalidate|.  Otherwise false.
 119   bool StaleWhileRevalidate(uint32_t now, uint32_t expiration);
 120
 121   // returns true if the server appears to support byte range requests.
 122   bool IsResumable();
 123
 124   // returns true if the Expires header has a value in the past relative to the
 125   // value of the Date header.
 126   bool ExpiresInPast();
 127
 128   // update headers...
 129   void UpdateHeaders(nsHttpResponseHead* aOther);
 130
 131   // reset the response head to it's initial state
 132   void Reset();
 133
 134   [[nodiscard]] nsresult GetLastModifiedValue(uint32_t* result);
 135
 136   bool operator==(const nsHttpResponseHead& aOther) const;
 137
 138   // Using this function it is possible to itereate through all headers
 139   // automatically under one lock.
 140   [[nodiscard]] nsresult VisitHeaders(nsIHttpHeaderVisitor* visitor,
 141                                       nsHttpHeaderArray::VisitorFilter filter);
 142   [[nodiscard]] nsresult GetOriginalHeader(const nsHttpAtom& aHeader,
 143                                            nsIHttpHeaderVisitor* aVisitor);
 144
 145   bool HasContentType() const;
 146   bool HasContentCharset();
 147   bool GetContentTypeOptionsHeader(nsACString& aOutput);
 148
 149  private:
 150   [[nodiscard]] nsresult SetHeader_locked(const nsHttpAtom& atom,
 151                                           const nsACString& h,
 152                                           const nsACString& v, bool m = false)
 153       MOZ_REQUIRES(mRecursiveMutex);
 154   void AssignDefaultStatusText() MOZ_REQUIRES(mRecursiveMutex);
 155   void ParseVersion(const char*) MOZ_REQUIRES(mRecursiveMutex);
 156   void ParseCacheControl(const char*) MOZ_REQUIRES(mRecursiveMutex);
 157   void ParsePragma(const char*) MOZ_REQUIRES(mRecursiveMutex);
 158   // Parses a content-length header-value as described in
 159   // https://fetch.spec.whatwg.org/#content-length-header
 160   nsresult ParseResponseContentLength(const nsACString& aHeaderStr)
 161       MOZ_REQUIRES(mRecursiveMutex);
 162
 163   nsresult ParseStatusLine_locked(const nsACString& line)
 164       MOZ_REQUIRES(mRecursiveMutex);
 165   [[nodiscard]] nsresult ParseHeaderLine_locked(const nsACString& line,
 166                                                 bool originalFromNetHeaders)
 167       MOZ_REQUIRES(mRecursiveMutex);
 168
 169   // these return failure if the header does not exist.
 170   [[nodiscard]] nsresult ParseDateHeader(const nsHttpAtom& header,
 171                                          uint32_t* result) const
 172       MOZ_REQUIRES(mRecursiveMutex);
 173   [[nodiscard]] nsresult GetAgeValue(uint32_t* result);
 174   [[nodiscard]] nsresult GetMaxAgeValue(uint32_t* result);
 175   [[nodiscard]] nsresult GetStaleWhileRevalidateValue(uint32_t* result);
 176   [[nodiscard]] nsresult GetDateValue(uint32_t* result);
 177   [[nodiscard]] nsresult GetExpiresValue(uint32_t* result);
 178
 179   bool ExpiresInPast_locked() const MOZ_REQUIRES(mRecursiveMutex);
 180   [[nodiscard]] nsresult GetAgeValue_locked(uint32_t* result) const
 181       MOZ_REQUIRES(mRecursiveMutex);
 182   [[nodiscard]] nsresult GetExpiresValue_locked(uint32_t* result) const
 183       MOZ_REQUIRES(mRecursiveMutex);
 184   [[nodiscard]] nsresult GetMaxAgeValue_locked(uint32_t* result) const
 185       MOZ_REQUIRES(mRecursiveMutex);
 186   [[nodiscard]] nsresult GetStaleWhileRevalidateValue_locked(
 187       uint32_t* result) const MOZ_REQUIRES(mRecursiveMutex);
 188
 189   [[nodiscard]] nsresult GetDateValue_locked(uint32_t* result) const
 190       MOZ_REQUIRES(mRecursiveMutex) {
 191     return ParseDateHeader(nsHttp::Date, result);
 192   }
 193
 194   [[nodiscard]] nsresult GetLastModifiedValue_locked(uint32_t* result) const
 195       MOZ_REQUIRES(mRecursiveMutex) {
 196     return ParseDateHeader(nsHttp::Last_Modified, result);
 197   }
 198
 199   bool NoCache_locked() const MOZ_REQUIRES(mRecursiveMutex) {
 200     // We ignore Pragma: no-cache if Cache-Control is set.
 201     MOZ_ASSERT_IF(mCacheControlNoCache, mHasCacheControl);
 202     return mHasCacheControl ? mCacheControlNoCache : mPragmaNoCache;
 203   }
 204
 205  private:
 206   // All members must be copy-constructable and assignable
 207   nsHttpHeaderArray mHeaders MOZ_GUARDED_BY(mRecursiveMutex);
 208   HttpVersion mVersion MOZ_GUARDED_BY(mRecursiveMutex){HttpVersion::v1_1};
 209   uint16_t mStatus MOZ_GUARDED_BY(mRecursiveMutex){200};
 210   nsCString mStatusText MOZ_GUARDED_BY(mRecursiveMutex);
 211   int64_t mContentLength MOZ_GUARDED_BY(mRecursiveMutex){-1};
 212   nsCString mContentType MOZ_GUARDED_BY(mRecursiveMutex);
 213   nsCString mContentCharset MOZ_GUARDED_BY(mRecursiveMutex);
 214   bool mHasCacheControl MOZ_GUARDED_BY(mRecursiveMutex){false};
 215   bool mCacheControlPublic MOZ_GUARDED_BY(mRecursiveMutex){false};
 216   bool mCacheControlPrivate MOZ_GUARDED_BY(mRecursiveMutex){false};
 217   bool mCacheControlNoStore MOZ_GUARDED_BY(mRecursiveMutex){false};
 218   bool mCacheControlNoCache MOZ_GUARDED_BY(mRecursiveMutex){false};
 219   bool mCacheControlImmutable MOZ_GUARDED_BY(mRecursiveMutex){false};
 220   bool mCacheControlStaleWhileRevalidateSet MOZ_GUARDED_BY(mRecursiveMutex){
 221       false};
 222   uint32_t mCacheControlStaleWhileRevalidate MOZ_GUARDED_BY(mRecursiveMutex){0};
 223   bool mCacheControlMaxAgeSet MOZ_GUARDED_BY(mRecursiveMutex){false};
 224   uint32_t mCacheControlMaxAge MOZ_GUARDED_BY(mRecursiveMutex){0};
 225   bool mPragmaNoCache MOZ_GUARDED_BY(mRecursiveMutex){false};
 226
 227   // We are using RecursiveMutex instead of a Mutex because VisitHeader
 228   // function calls nsIHttpHeaderVisitor::VisitHeader while under lock.
 229   mutable RecursiveMutex mRecursiveMutex{"nsHttpResponseHead.mRecursiveMutex"};
 230   // During VisitHeader we sould not allow call to SetHeader.
 231   bool mInVisitHeaders MOZ_GUARDED_BY(mRecursiveMutex){false};
 232
 233   friend struct IPC::ParamTraits<nsHttpResponseHead>;
 234 };
 235
 236 }  // namespace net
 237 }  // namespace mozilla
 238
 239 #endif  // nsHttpResponseHead_h__