| /* |
| * Copyright (C) 2009 Google Inc. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions are |
| * met: |
| * |
| * * Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * * Redistributions in binary form must reproduce the above |
| * copyright notice, this list of conditions and the following disclaimer |
| * in the documentation and/or other materials provided with the |
| * distribution. |
| * * Neither the name of Google Inc. nor the names of its |
| * contributors may be used to endorse or promote products derived from |
| * this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #include "config.h" |
| #include "BindingSecurityBase.h" |
| |
| #include "DOMWindow.h" |
| #include "Frame.h" |
| #include "SecurityOrigin.h" |
| |
| namespace WebCore { |
| |
| DOMWindow* BindingSecurityBase::getDOMWindow(Frame* frame) |
| { |
| return frame->domWindow(); |
| } |
| |
| Frame* BindingSecurityBase::getFrame(Node* node) |
| { |
| return node->document()->frame(); |
| } |
| |
| // Same origin policy implementation: |
| // |
| // Same origin policy prevents JS code from domain A from accessing JS & DOM |
| // objects in a different domain B. There are exceptions and several objects |
| // are accessible by cross-domain code. For example, the window.frames object |
| // is accessible by code from a different domain, but window.document is not. |
| // |
| // The JS binding code sets security check callbacks on a function template, |
| // and accessing instances of the template calls the callback function. |
| // The callback function enforces the same origin policy. |
| // |
| // Callback functions are expensive. Binding code should use a security token |
| // string to do fast access checks for the common case where source and target |
| // are in the same domain. A security token is a string object that represents |
| // the protocol/url/port of a domain. |
| // |
| // There are special cases where security token matching is not enough. |
| // For example, JS can set its domain to a super domain by calling |
| // document.setDomain(...). In these cases, the binding code can reset |
| // a context's security token to its global object so that the fast access |
| // check will always fail. |
| |
| // Helper to check if the current execution context can access a target frame. |
| // First it checks same domain policy using the lexical context. |
| // |
| // This is equivalent to KJS::Window::allowsAccessFrom(ExecState*). |
| bool BindingSecurityBase::canAccess(DOMWindow* activeWindow, |
| DOMWindow* targetWindow) |
| { |
| ASSERT(targetWindow); |
| |
| String message; |
| |
| if (activeWindow == targetWindow) |
| return true; |
| |
| if (!activeWindow) |
| return false; |
| |
| const SecurityOrigin* activeSecurityOrigin = activeWindow->securityOrigin(); |
| const SecurityOrigin* targetSecurityOrigin = targetWindow->securityOrigin(); |
| |
| // We have seen crashes were the security origin of the target has not been |
| // initialized. Defend against that. |
| if (!targetSecurityOrigin) |
| return false; |
| |
| if (activeSecurityOrigin->canAccess(targetSecurityOrigin)) |
| return true; |
| |
| // Allow access to a "about:blank" page if the dynamic context is a |
| // detached context of the same frame as the blank page. |
| if (targetSecurityOrigin->isEmpty() && activeWindow->frame() == targetWindow->frame()) |
| return true; |
| |
| return false; |
| } |
| |
| } // namespace WebCore |