[tbb-commits] [tor-browser/tor-browser-24.7.0esr-4.x-2] fixup! Bug #6253: Add canvas image extraction prompt.

[mikeperry at torproject.org]

commit 3ef809fcfc22b0d46a52a3393cc685f44b66180e
Author: Mike Perry <mikeperry-git at torproject.org>
Date:   Tue Aug 19 20:34:23 2014 -0700

    fixup! Bug #6253: Add canvas image extraction prompt.
    
    Use JSContext to get URL information for HTML5 canvas access.
---
 content/canvas/src/CanvasRenderingContext2D.cpp |    2 +-
 content/canvas/src/CanvasUtils.cpp              |   18 +++++++++++++-----
 content/canvas/src/CanvasUtils.h                |    2 +-
 content/html/content/src/HTMLCanvasElement.cpp  |    9 +++++----
 4 files changed, 20 insertions(+), 11 deletions(-)

diff --git a/content/canvas/src/CanvasRenderingContext2D.cpp b/content/canvas/src/CanvasRenderingContext2D.cpp
index 9be4ced..c53ac07 100644
--- a/content/canvas/src/CanvasRenderingContext2D.cpp
+++ b/content/canvas/src/CanvasRenderingContext2D.cpp
@@ -3506,7 +3506,7 @@ CanvasRenderingContext2D::GetImageDataArray(JSContext* aCx,
   if (mCanvasElement) {
     nsCOMPtr<nsIDocument> ownerDoc = mCanvasElement->OwnerDoc();
     usePlaceholder = !ownerDoc ||
-                        !CanvasUtils::IsImageExtractionAllowed(ownerDoc);
+      !CanvasUtils::IsImageExtractionAllowed(ownerDoc, aCx);
   }
 
   if (usePlaceholder) {
diff --git a/content/canvas/src/CanvasUtils.cpp b/content/canvas/src/CanvasUtils.cpp
index f2f4536..591650a 100644
--- a/content/canvas/src/CanvasUtils.cpp
+++ b/content/canvas/src/CanvasUtils.cpp
@@ -35,6 +35,7 @@ using namespace mozilla::gfx;
 #include "nsUnicharUtils.h"
 #include "nsPrintfCString.h"
 #include "nsIConsoleService.h"
+#include "jsdbgapi.h"
 
 #define TOPIC_CANVAS_PERMISSIONS_PROMPT "canvas-permissions-prompt"
 #define PERMISSION_CANVAS_EXTRACT_DATA "canvas/extractData"
@@ -43,10 +44,9 @@ namespace mozilla {
 namespace CanvasUtils {
 
 // Check site-specific permission and display prompt if appropriate.
-bool
-IsImageExtractionAllowed(nsIDocument *aDocument)
+bool IsImageExtractionAllowed(nsIDocument *aDocument, JSContext *aCx)
 {
-  if (!aDocument)
+  if (!aDocument || !aCx)
     return false;
 
   nsPIDOMWindow *win = aDocument->GetWindow();
@@ -87,13 +87,21 @@ IsImageExtractionAllowed(nsIDocument *aDocument)
         rv = thirdPartyUtil->IsThirdPartyURI(uri, docURI, &isThirdParty);
         NS_ENSURE_SUCCESS(rv, false);
 
+        nsCString scriptFile("unknown");
+        unsigned scriptLine = 0;
+        JSScript *script;
+        if (JS_DescribeScriptedCaller(aCx, &script, &scriptLine)) {
+          scriptFile = JS_GetScriptFilename(aCx, script);
+        }
+
         nsCString firstPartySpec;
         rv = uri->GetSpec(firstPartySpec);
         nsCString docSpec;
         docURI->GetSpec(docSpec);
         nsPrintfCString msg("On %s: blocked access to canvas image data"
-                            " from %s ",  // L10n
-                            firstPartySpec.get(), docSpec.get());
+                            " from document %s, script from %s:%u ",  // L10n
+                            firstPartySpec.get(), docSpec.get(),
+                            scriptFile.get(), scriptLine);
 
         nsCOMPtr<nsIConsoleService> console
                               (do_GetService(NS_CONSOLESERVICE_CONTRACTID));
diff --git a/content/canvas/src/CanvasUtils.h b/content/canvas/src/CanvasUtils.h
index d7aae4d..1e7f726 100644
--- a/content/canvas/src/CanvasUtils.h
+++ b/content/canvas/src/CanvasUtils.h
@@ -45,7 +45,7 @@ void DoDrawImageSecurityCheck(dom::HTMLCanvasElement *aCanvasElement,
                               bool forceWriteOnly,
                               bool CORSUsed);
 
-bool IsImageExtractionAllowed(nsIDocument *aDocument);
+bool IsImageExtractionAllowed(nsIDocument *aDocument, JSContext *aCx);
 
 // Make a double out of |v|, treating undefined values as 0.0 (for
 // the sake of sparse arrays).  Return true iff coercion
diff --git a/content/html/content/src/HTMLCanvasElement.cpp b/content/html/content/src/HTMLCanvasElement.cpp
index e229e1c..d6cb88a 100644
--- a/content/html/content/src/HTMLCanvasElement.cpp
+++ b/content/html/content/src/HTMLCanvasElement.cpp
@@ -355,7 +355,7 @@ HTMLCanvasElement::ToDataURL(const nsAString& aType, const JS::Value& aParams,
 
   // Check site-specific permission and display prompt if appropriate.
   // If no permission, return all-white, opaque image data.
-  bool usePlaceholder = !CanvasUtils::IsImageExtractionAllowed(OwnerDoc());
+  bool usePlaceholder = !CanvasUtils::IsImageExtractionAllowed(OwnerDoc(), aCx);
   return ToDataURLImpl(aCx, aType, aParams, usePlaceholder, aDataURL);
 }
 
@@ -590,10 +590,11 @@ HTMLCanvasElement::ToBlob(nsIFileCallback* aCallback,
   }
 
   bool fallbackToPNG = false;
+  JSContext* cx = nsContentUtils::GetCurrentJSContext();
 
   // Check site-specific permission and display prompt if appropriate.
   // If no permission, return all-white, opaque image data.
-  bool usePlaceholder = !CanvasUtils::IsImageExtractionAllowed(OwnerDoc());
+  bool usePlaceholder = !CanvasUtils::IsImageExtractionAllowed(OwnerDoc(), cx);
   nsCOMPtr<nsIInputStream> stream;
   rv = ExtractData(type, EmptyString(), usePlaceholder,
                    getter_AddRefs(stream), fallbackToPNG);
@@ -616,7 +617,6 @@ HTMLCanvasElement::ToBlob(nsIFileCallback* aCallback,
   nsRefPtr<nsDOMMemoryFile> blob =
     new nsDOMMemoryFile(imgData, imgSize, type);
 
-  JSContext* cx = nsContentUtils::GetCurrentJSContext();
   if (cx) {
     JS_updateMallocCounter(cx, imgSize);
   }
@@ -648,7 +648,8 @@ HTMLCanvasElement::MozGetAsFile(const nsAString& aName,
 
   // Check site-speciifc permission and display prompt if appropriate.
   // If no permission, return all-white, opaque image data.
-  bool usePlaceholder = !CanvasUtils::IsImageExtractionAllowed(OwnerDoc());
+  bool usePlaceholder = !CanvasUtils::IsImageExtractionAllowed(OwnerDoc(),
+                         nsContentUtils::GetCurrentJSContext());
   return MozGetAsFileImpl(aName, aType, usePlaceholder, aResult);
 }