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/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include <stdlib.h>
#include <stdarg.h>
#include "prprf.h"
#include "nsIServiceManager.h"
#include "nsIConsoleService.h"
#include "nsIDOMCanvasRenderingContext2D.h"
#include "nsICanvasRenderingContextInternal.h"
#include "nsIHTMLCollection.h"
#include "mozilla/dom/HTMLCanvasElement.h"
#include "nsIPrincipal.h"
#include "nsGfxCIID.h"
#include "nsTArray.h"
#include "CanvasUtils.h"
#include "mozilla/gfx/Matrix.h"
#include "WebGL2Context.h"
using namespace mozilla::gfx;
namespace mozilla {
namespace CanvasUtils {
bool
GetCanvasContextType(const nsAString& str, dom::CanvasContextType* const out_type)
{
if (str.EqualsLiteral("2d")) {
*out_type = dom::CanvasContextType::Canvas2D;
return true;
}
if (str.EqualsLiteral("experimental-webgl")) {
*out_type = dom::CanvasContextType::WebGL1;
return true;
}
#ifdef MOZ_WEBGL_CONFORMANT
if (str.EqualsLiteral("webgl")) {
/* WebGL 1.0, $2.1 "Context Creation":
* If the user agent supports both the webgl and experimental-webgl
* canvas context types, they shall be treated as aliases.
*/
*out_type = dom::CanvasContextType::WebGL1;
return true;
}
#endif
if (WebGL2Context::IsSupported()) {
if (str.EqualsLiteral("webgl2")) {
*out_type = dom::CanvasContextType::WebGL2;
return true;
}
}
if (str.EqualsLiteral("bitmaprenderer")) {
*out_type = dom::CanvasContextType::ImageBitmap;
return true;
}
return false;
}
/**
* This security check utility might be called from an source that never taints
* others. For example, while painting a CanvasPattern, which is created from an
* ImageBitmap, onto a canvas. In this case, the caller could set the CORSUsed
* true in order to pass this check and leave the aPrincipal to be a nullptr
* since the aPrincipal is not going to be used.
*/
void
DoDrawImageSecurityCheck(dom::HTMLCanvasElement *aCanvasElement,
nsIPrincipal *aPrincipal,
bool forceWriteOnly,
bool CORSUsed)
{
// Callers should ensure that mCanvasElement is non-null before calling this
if (!aCanvasElement) {
NS_WARNING("DoDrawImageSecurityCheck called without canvas element!");
return;
}
if (aCanvasElement->IsWriteOnly())
return;
// If we explicitly set WriteOnly just do it and get out
if (forceWriteOnly) {
aCanvasElement->SetWriteOnly();
return;
}
// No need to do a security check if the image used CORS for the load
if (CORSUsed)
return;
NS_PRECONDITION(aPrincipal, "Must have a principal here");
if (aCanvasElement->NodePrincipal()->Subsumes(aPrincipal)) {
// This canvas has access to that image anyway
return;
}
aCanvasElement->SetWriteOnly();
}
bool
CoerceDouble(const JS::Value& v, double* d)
{
if (v.isDouble()) {
*d = v.toDouble();
} else if (v.isInt32()) {
*d = double(v.toInt32());
} else if (v.isUndefined()) {
*d = 0.0;
} else {
return false;
}
return true;
}
bool CheckWriteOnlySecurity(bool aCORSUsed, nsIPrincipal* aPrincipal) {
if (!aPrincipal) {
return true;
}
if (!aCORSUsed) {
nsIGlobalObject* incumbentSettingsObject = dom::GetIncumbentGlobal();
if (NS_WARN_IF(!incumbentSettingsObject)) {
return true;
}
nsIPrincipal* principal = incumbentSettingsObject->PrincipalOrNull();
if (NS_WARN_IF(!principal) || !(principal->Subsumes(aPrincipal))) {
return true;
}
}
return false;
}
} // namespace CanvasUtils
} // namespace mozilla
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