Bug 1267474 - cache-control: immutable 2/3 r=mayhemer

--HG--
extra : rebase_source : 5022699f221ecd3cb66336ef11c6863b89e8de88

netwerk/base/nsIRequest.idl

@@ -180,7 +180,7 @@ interface nsIRequest : nsISupports
      * cached content is automatically validated if necessary before reuse.
      * 
      * VALIDATE_ALWAYS forces validation of any cached content independent of
-     * its expiration time.
+     * its expiration time (unless it is https with Cache-Control: immutable)
      * 
      * VALIDATE_NEVER disables validation of cached content, unless it arrived
      * with the "Cache: no-store" header, or arrived via HTTPS with the

netwerk/protocol/http/nsHttpChannel.cpp

@@ -3407,6 +3407,13 @@ nsHttpChannel::OnCacheEntryCheck(nsICacheEntry* entry, nsIApplicationCache* appC
     bool isForcedValid = false;
     entry->GetIsForcedValid(&isForcedValid);
 
+    nsXPIDLCString framedBuf;
+    rv = entry->GetMetaDataElement("strongly-framed", getter_Copies(framedBuf));
+    // describe this in terms of explicitly weakly framed so as to be backwards
+    // compatible with old cache contents which dont have strongly-framed makers
+    bool weaklyFramed = NS_SUCCEEDED(rv) && framedBuf.EqualsLiteral("0");
+    bool isImmutable = !weaklyFramed && isHttps && mCachedResponseHead->Immutable();
+
     // Cached entry is not the entity we request (see bug #633743)
     if (ResponseWouldVary(entry)) {
         LOG(("Validating based on Vary headers returning TRUE\n"));
@@ -3432,7 +3439,7 @@ nsHttpChannel::OnCacheEntryCheck(nsICacheEntry* entry, nsIApplicationCache* appC
     }
     // If the VALIDATE_ALWAYS flag is set, any cached data won't be used until
     // it's revalidated with the server.
-    else if (mLoadFlags & nsIRequest::VALIDATE_ALWAYS) {
+    else if ((mLoadFlags & nsIRequest::VALIDATE_ALWAYS) && !isImmutable) {
         LOG(("Validating based on VALIDATE_ALWAYS load flag\n"));
         doValidation = true;
     }
@@ -3559,12 +3566,6 @@ nsHttpChannel::OnCacheEntryCheck(nsICacheEntry* entry, nsIApplicationCache* appC
     mCachedContentIsValid = !doValidation;
 
     if (doValidation) {
-        nsXPIDLCString buf;
-        rv = entry->GetMetaDataElement("strongly-framed", getter_Copies(buf));
-        // describe this in terms of explicitly weakly framed so as to be backwards
-        // compatible with old cache contents which dont have strongly-framed makers
-        bool weaklyFramed = NS_SUCCEEDED(rv) && buf.EqualsLiteral("0");
-
         //
         // now, we are definitely going to issue a HTTP request to the server.
         // make it conditional if possible.
@@ -3576,12 +3577,12 @@ nsHttpChannel::OnCacheEntryCheck(nsICacheEntry* entry, nsIApplicationCache* appC
         // the request method MUST be either GET or HEAD (see bug 175641) and
         // the cached response code must be < 400
         //
-        // the cached content must not be weakly framed
+        // the cached content must not be weakly framed or marked immutable
         //
         // do not override conditional headers when consumer has defined its own
         if (!mCachedResponseHead->NoStore() &&
             (mRequestHead.IsGet() || mRequestHead.IsHead()) &&
-            !mCustomConditionalRequest && !weaklyFramed &&
+            !mCustomConditionalRequest && !weaklyFramed && !isImmutable &&
             (mCachedResponseHead->Status() < 400)) {
 
             if (mConcurentCacheAccess) {

netwerk/protocol/http/nsHttpResponseHead.cpp

@@ -643,6 +643,7 @@ nsHttpResponseHead::Reset()
     mCacheControlPrivate = false;
     mCacheControlNoStore = false;
     mCacheControlNoCache = false;
+    mCacheControlImmutable = false;
     mPragmaNoCache = false;
     mStatusText.Truncate();
     mContentType.Truncate();
@@ -812,6 +813,7 @@ nsHttpResponseHead::ParseCacheControl(const char *val)
         mCacheControlPrivate = false;
         mCacheControlNoCache = false;
         mCacheControlNoStore = false;
+        mCacheControlImmutable = false;
         return;
     }
 
@@ -827,6 +829,11 @@ nsHttpResponseHead::ParseCacheControl(const char *val)
     // search header value for occurrence of "no-store"
     if (nsHttp::FindToken(val, "no-store", HTTP_HEADER_VALUE_SEPS))
         mCacheControlNoStore = true;
+
+    // search header value for occurrence of "immutable"
+    if (nsHttp::FindToken(val, "immutable", HTTP_HEADER_VALUE_SEPS)) {
+        mCacheControlImmutable = true;
+    }
 }
 
 void

netwerk/protocol/http/nsHttpResponseHead.h

@@ -32,6 +32,7 @@ public:
                          , mCacheControlPrivate(false)
                          , mCacheControlNoStore(false)
                          , mCacheControlNoCache(false)
+                         , mCacheControlImmutable(false)
                          , mPragmaNoCache(false) {}
 
     const nsHttpHeaderArray & Headers()   const { return mHeaders; }
@@ -47,6 +48,7 @@ public:
     bool                  Private() const { return mCacheControlPrivate; }
     bool                  NoStore() const { return mCacheControlNoStore; }
     bool                  NoCache() const { return (mCacheControlNoCache || mPragmaNoCache); }
+    bool                  Immutable() const { return mCacheControlImmutable; }
     /**
      * Full length of the entity. For byte-range requests, this may be larger
      * than ContentLength(), which will only represent the requested part of the
@@ -133,6 +135,7 @@ public:
                mCacheControlPrivate == aOther.mCacheControlPrivate &&
                mCacheControlNoCache == aOther.mCacheControlNoCache &&
                mCacheControlNoStore == aOther.mCacheControlNoStore &&
+               mCacheControlImmutable == aOther.mCacheControlImmutable &&
                mPragmaNoCache == aOther.mPragmaNoCache;
     }
 
@@ -154,6 +157,7 @@ private:
     bool              mCacheControlPrivate;
     bool              mCacheControlNoStore;
     bool              mCacheControlNoCache;
+    bool              mCacheControlImmutable;
     bool              mPragmaNoCache;
 
     friend struct IPC::ParamTraits<nsHttpResponseHead>;