Bug 1209184: Part 2 - [webext] Localize CSS files served from moz-extension: channels. r=jdm

netwerk/protocol/res/ExtensionProtocolHandler.cpp

@@ -8,6 +8,16 @@
 
 #include "nsIAddonPolicyService.h"
 #include "nsServiceManagerUtils.h"
+#include "nsIURL.h"
+#include "nsIChannel.h"
+#include "nsIStreamListener.h"
+#include "nsIRequestObserver.h"
+#include "nsIInputStreamChannel.h"
+#include "nsIInputStream.h"
+#include "nsIOutputStream.h"
+#include "nsIStreamConverterService.h"
+#include "nsIPipe.h"
+#include "nsNetUtil.h"
 
 namespace mozilla {
 
@@ -33,4 +43,107 @@ ExtensionProtocolHandler::GetFlagsForURI(nsIURI* aURI, uint32_t* aFlags)
   return NS_OK;
 }
 
+class PipeCloser : public nsIRequestObserver
+{
+public:
+  NS_DECL_ISUPPORTS
+
+  explicit PipeCloser(nsIOutputStream* aOutputStream) :
+    mOutputStream(aOutputStream)
+  {
+  }
+
+  NS_IMETHOD OnStartRequest(nsIRequest*, nsISupports*) override
+  {
+    return NS_OK;
+  }
+
+  NS_IMETHOD OnStopRequest(nsIRequest*, nsISupports*, nsresult aStatusCode) override
+  {
+    NS_ENSURE_TRUE(mOutputStream, NS_ERROR_UNEXPECTED);
+
+    nsresult rv = mOutputStream->Close();
+    mOutputStream = nullptr;
+    return rv;
+  }
+
+protected:
+  virtual ~PipeCloser() {}
+
+private:
+  nsCOMPtr<nsIOutputStream> mOutputStream;
+};
+
+NS_IMPL_ISUPPORTS(PipeCloser, nsIRequestObserver)
+
+nsresult
+ExtensionProtocolHandler::SubstituteChannel(nsIURI* aURI,
+                                            nsILoadInfo* aLoadInfo,
+                                            nsIChannel** result)
+{
+  nsresult rv;
+  nsCOMPtr<nsIURL> url = do_QueryInterface(aURI, &rv);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  nsAutoCString ext;
+  rv = url->GetFileExtension(ext);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  if (!ext.LowerCaseEqualsLiteral("css")) {
+    return NS_OK;
+  }
+
+  // Filter CSS files to replace locale message tokens with localized strings.
+
+  nsCOMPtr<nsIStreamConverterService> convService =
+    do_GetService(NS_STREAMCONVERTERSERVICE_CONTRACTID, &rv);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  const char* kFromType = "application/vnd.mozilla.webext.unlocalized";
+  const char* kToType = "text/css";
+
+  nsCOMPtr<nsIInputStream> inputStream;
+  if (aLoadInfo && aLoadInfo->GetSecurityMode()) {
+    // Certain security checks require an async channel.
+
+    nsCOMPtr<nsIOutputStream> outputStream;
+    rv = NS_NewPipe(getter_AddRefs(inputStream), getter_AddRefs(outputStream),
+                    0, UINT32_MAX, true, false);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    nsCOMPtr<nsIStreamListener> listener;
+    nsCOMPtr<nsIRequestObserver> observer = new PipeCloser(outputStream);
+    rv = NS_NewSimpleStreamListener(getter_AddRefs(listener), outputStream, observer);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    nsCOMPtr<nsIStreamListener> converter;
+    rv = convService->AsyncConvertData(kFromType, kToType, listener,
+                                       aURI, getter_AddRefs(converter));
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    rv = (*result)->AsyncOpen2(converter);
+  } else {
+    // Stylesheet loads for extension content scripts require a sync channel,
+    // but fortunately do not invoke security checks.
+
+    nsCOMPtr<nsIInputStream> sourceStream;
+    rv = (*result)->Open(getter_AddRefs(sourceStream));
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    rv = convService->Convert(sourceStream, kFromType, kToType,
+                              aURI, getter_AddRefs(inputStream));
+  }
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  nsCOMPtr<nsIChannel> channel;
+  rv = NS_NewInputStreamChannelInternal(getter_AddRefs(channel), aURI, inputStream,
+                                        NS_LITERAL_CSTRING("text/css"),
+                                        NS_LITERAL_CSTRING("utf-8"),
+                                        aLoadInfo);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  channel.swap(*result);
+  return NS_OK;
+}
+
 } // namespace mozilla

netwerk/protocol/res/ExtensionProtocolHandler.h

@@ -39,6 +39,8 @@ protected:
 
     return false;
   }
+
+  virtual nsresult SubstituteChannel(nsIURI* uri, nsILoadInfo* aLoadInfo, nsIChannel** result) override;
 };
 
 } // namespace mozilla

netwerk/protocol/res/SubstitutingProtocolHandler.cpp

@@ -253,7 +253,10 @@ SubstitutingProtocolHandler::NewChannel2(nsIURI* uri,
   nsLoadFlags loadFlags = 0;
   (*result)->GetLoadFlags(&loadFlags);
   (*result)->SetLoadFlags(loadFlags & ~nsIChannel::LOAD_REPLACE);
-  return (*result)->SetOriginalURI(uri);
+  rv = (*result)->SetOriginalURI(uri);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  return SubstituteChannel(uri, aLoadInfo, result);
 }
 
 nsresult

netwerk/protocol/res/SubstitutingProtocolHandler.h

@@ -59,6 +59,13 @@ protected:
     return false;
   }
 
+  // Override this in the subclass to check for special case when opening
+  // channels.
+  virtual nsresult SubstituteChannel(nsIURI* uri, nsILoadInfo* aLoadInfo, nsIChannel** result)
+  {
+    return NS_OK;
+  }
+
   nsIIOService* IOService() { return mIOService; }
 
 private: